agent

When you're buying a house or negotiating your break-out movie contract, it's a good idea to hire an agent to represent you — someone who can keep a cool head and get the best deal for you.

The suave 007 may be your dream secret agent, but you could find real ones in the CIA, the FBI, and other government organizations populated with agents. Beware the double agent, the spy you think is working for you when he's really working for your enemy. An inanimate object can also be an agent. A chemical agent, like vinegar mixed with salt, can make copper pennies shine. Chemical weapons contain more sinister agents that wreak havoc on their victims.

Definitions of agent
  1. noun
    a representative who acts on behalf of other persons or organizations
    see moresee less
    types:
    show 35 types...
    hide 35 types...
    business agent
    an agent who handles business affairs for another; especially one who deals with employers
    literary agent
    an agent who represents an author in dealings with publishers
    bailee
    the agent to whom property involved in a bailment is delivered
    booker, booking agent
    someone who engages a person or company for performances
    deputy, surrogate
    a person appointed to represent or act on behalf of others
    employment agent
    someone who runs an employment agency
    freight agent
    an employee of a freight carrier who directs the receipt and delivery of goods
    government agent
    a representative or official of a government or administrative department of a government
    handler
    an agent who handles something or someone
    mill agent
    the responsible official at a mill that is under absentee ownership
    next friend
    (law) a person who acts on behalf of an infant or disabled person
    parliamentary agent
    a person who is employed to look after the affairs of businesses that are affected by legislation of the British Parliament
    placeholder, procurator, proxy
    a person authorized to act for another
    purchasing agent
    an agent who purchases goods or services for another
    intelligence agent, intelligence officer, operative, secret agent
    a person secretly employed in espionage for a government
    shipping agent
    the agent of a shipowner
    shopper
    a commercial agent who shops at the competitor's store in order to compare their prices and merchandise with those of the store that employs her
    special agent
    someone whose authority is limited to the special undertaking they have been instructed to perform
    talent agent
    an agent who represents performers
    general agent, universal agent
    someone authorized to transact every kind of business for the principal
    actor's agent, theatrical agent
    a business agent for an actor
    agent-in-place
    an operative serving as a penetration into an intelligence target
    agent provocateur, provocateur
    a secret agent who incites suspected persons to commit illegal acts
    bridge agent
    an operative who acts as a courier or go-between from a case officer to a secret agent in a hostile area
    case officer
    an operative who also serves as an official staffer of an intelligence service
    codetalker, windtalker
    a secret agent who was one of the Navajos who devised and used a code based on their native language; the code was unbroken by the Japanese during World War II
    foot
    a member of a surveillance team who works on foot or rides as a passenger
    FBI agent, G-man, government man
    a special law-enforcement agent of the Federal Bureau of Investigation
    NOC
    an undercover agent who is given no official cover
    revenuer
    a government agent responsible for collecting revenue (especially one responsible for stopping bootlegging)
    impresario, promoter, showman
    a sponsor who books and stages public entertainments
    spy, undercover agent
    (military) a secret agent hired by a state to obtain information about its enemies or by a business to obtain industrial secrets from competitors
    T-man
    a special law-enforcement agent of the United States Treasury
    vicegerent
    someone appointed by a ruler as an administrative deputy
    walk-in
    an operative who initiates his own defection (usually to a hostile country) for political asylum
    type of:
    representative
    a person who represents others
  2. noun
    any agent or representative of a federal agency or bureau
    synonyms: federal agent
    see moresee less
    types:
    Indian agent
    a representative of the federal government to American Indian tribes (especially on Indian reservations)
    Fed, Federal, federal official
    any federal law-enforcement officer
    trustbuster
    a federal agent who engages in trust busting
    type of:
    functionary, official
    a worker who holds or is invested with an office
  3. noun
    a businessperson who buys or sells for another in exchange for a commission
    synonyms: broker, factor
    see moresee less
    types:
    show 10 types...
    hide 10 types...
    auctioneer
    an agent who conducts an auction
    general agent, insurance agent, insurance broker, underwriter
    an agent who sells insurance
    investment banker, underwriter
    a banker who deals chiefly in underwriting new securities
    estate agent, house agent, land agent, real estate agent, real estate broker
    a person who is authorized to act as an agent for the sale of land
    ship broker
    an agent for the ship owner; obtains cargo and may arrange for its loading or discharge
    stockbroker
    an agent in the buying and selling of stocks and bonds
    syndic
    one appointed to represent a city or university or corporation in business transactions
    travel agent
    someone who sells or arranges trips or tours for customers
    killer bee
    an investment banker who devises strategies to make a target company less attractive for takeover
    Realtor
    a real estate agent who is a member of the National Association of Realtors
    type of:
    bourgeois, businessperson
    a capitalist who engages in industrial commercial enterprise
  4. noun
    a substance that exerts some force or effect
    see moresee less
    types:
    show 98 types...
    hide 98 types...
    antiflatulent
    any agent that reduces intestinal gas
    antifungal, antifungal agent, antimycotic, antimycotic agent, fungicide
    any agent that destroys or prevents the growth of fungi
    antimicrobial, antimicrobic, disinfectant, germicide
    an agent (as heat or radiation or a chemical) that destroys microorganisms that might carry disease
    drug
    a substance that is used as a medicine or narcotic
    vermicide
    an agent that kills worms (especially those in the intestines)
    alkaliser, alkalizer, antacid, antiacid, gastric antacid
    an agent that counteracts or neutralizes acidity (especially in the stomach)
    bacteriostat
    a chemical or biological material that inhibits bacterial growth
    blanching agent, bleach, bleaching agent, whitener
    an agent that makes things white or colorless
    chemical agent
    an agent that produces chemical reactions
    coagulant, coagulator
    an agent that produces coagulation
    coolant
    a fluid agent (gas or liquid) that produces cooling; especially one used to cool a system by transferring heat away from one part to another
    diluent, dilutant, thinner
    a diluting agent
    emmenagogue
    any agent that promotes menstrual discharge
    galactagogue
    agent that induces milk secretion
    hypnagogue
    an agent that induces drowsiness or sleep
    hypoglycaemic agent, hypoglycemic agent
    any of various agents that decrease the level of glucose in the blood and are used in the treatment of diabetes mellitus
    inducer
    an agent capable of activating specific genes
    lactifuge
    any agent that reduces milk secretion (as given to a woman who is not breast feeding)
    lactogen
    any agent that enhances milk production
    mitogen
    an agent that triggers mitosis
    nerve agent, nerve gas
    a toxic gas that is inhaled or absorbed through the skin and has harmful effects on the nervous and respiratory system
    precipitant
    an agent that causes a precipitate to form
    solvating agent
    an agent that converts something into a solvate
    viricide, virucide
    an agent (physical or chemical) that inactivates or destroys viruses
    aborticide, abortifacient, abortion-inducing drug
    a drug (or other chemical agent) that causes abortion
    agonist
    (biochemistry) a drug that can combine with a receptor on a cell to produce a physiological reaction
    anaesthetic, anaesthetic agent, anesthesia, anesthetic, anesthetic agent
    a drug that causes temporary loss of bodily sensations
    antagonist
    a drug that neutralizes or counteracts the effects of another drug
    antisyphilitic
    a drug (or other chemical agent) that is effective against syphilis
    anti-TNF compound
    a class of drugs that block the action of tumor necrosis factor (TNF); used in cases of rheumatoid arthritis because TNF instigates inflammation of the joints
    Bordeaux mixture
    antifungal agent consisting of a solution of copper sulphate and quicklime
    botanical
    a drug made from part of a plant (as the bark or root or leaves)
    brand-name drug, proprietary drug
    a drug that has a trade name and is protected by a patent (can be produced and sold only by the company holding the patent)
    Tagamet, cimetidine
    a drug (trade name Tagamet) used to treat peptic ulcers by decreasing the secretion of stomach acid
    controlled substance
    a drug or chemical substance whose possession and use are controlled by law
    dilator
    a drug that causes dilation
    diuretic, diuretic drug, water pill
    any substance that tends to increase the flow of urine, which causes the body to get rid of excess water
    drug of abuse, street drug
    a drug that is taken for nonmedicinal reasons (usually for mind-altering effects); drug abuse can lead to physical and mental damage and (with some substances) dependence and addiction
    Feosol
    trade name of a drug rich in iron; used to treat some kinds of anemia
    Fergon
    trade name of a drug rich in iron; used to treat some types of anemia
    fertility drug
    a drug used to increase a woman's fertility
    generic drug
    when the patent protection for a brand-name drug expires generic versions of the drug can be offered for sale if the FDA agrees
    Fulvicin, griseofulvin
    a kind of penicillin (a fungicidal antibiotic with the trade name Fulvicin) produced by molds of the genus Penicillium
    intoxicant
    a drug that can produce a state of intoxication
    Clioquinol, iodochlorhydroxyquin
    drug used to treat certain fungal infection (as athlete's foot)
    Sporanox, itraconazole
    an oral antifungal drug (trade name Sporanox) taken for cases of fungal nail disease
    Lorfan, levallorphan
    drug (trade name Lorfan) that is related to morphine but that counteracts the respiratory depression produced by morphine poisoning but without affecting its analgesic effects
    medicament, medication, medicinal drug, medicine
    (medicine) something that treats or prevents or alleviates the symptoms of disease
    Monistat, miconazole
    an antifungal agent usually administered in the form of a nitrate (trade name Monistat)
    miotic, miotic drug, myotic, myotic drug
    a drug that causes miosis (constriction of the pupil of the eye)
    mydriatic, mydriatic drug
    a drug that causes the pupil of the eye to dilate; used to aid eye examinations
    narcotic
    a drug that produces numbness or stupor; often taken for pleasure or to reduce pain; extensive use can lead to addiction
    Mycostatin, Nystan, nystatin
    an antifungal and antibiotic (trade names Mycostatin and Nystan) discovered in New York State; derived from soil fungi actinomycetes
    Trental, pentoxifylline
    a drug (trade name Trental) used to treat claudication; believed to increase the flexibility of red blood cells so they can flow through the blood vessels to the legs and feet
    consciousness-altering drug, mind-altering drug, psychoactive drug, psychoactive substance
    a drug that can produce mood changes and distorted perceptions
    psychotropic agent
    a chemical substance that can influence human consciousness
    Zantac, ranitidine
    a histamine blocker and antacid (trade name Zantac) used to treat peptic ulcers and gastritis and esophageal reflux
    relaxant
    a drug that relaxes and relieves tension
    hypnotic, soporific
    a drug that induces sleep
    excitant, stimulant, stimulant drug
    a drug that temporarily quickens some vital process
    appetite suppressant, suppressant
    a drug that suppresses appetite
    synergist
    a drug that augments the activity of another drug
    Lamisil, terbinafine
    an oral antifungal drug (trade name Lamisil) used to treat cases of fungal nail disease
    thiabendazole
    an antifungal agent and anthelmintic
    Orinase, tolbutamide
    sulfonylurea; an oral antidiabetic drug (trade name Orinase) used in the treatment of adult-onset diabetes mellitus
    anti-impotence drug, virility drug
    drug to treat impotence attributable to erectile dysfunction
    insulin
    hormone secreted by the isles of Langerhans in the pancreas; regulates storage of glycogen in the liver and accelerates oxidation of sugar in cells
    arsenical
    a pesticide or drug containing arsenic
    lactogenic hormone, luteotropin, prolactin
    gonadotropic hormone secreted by the anterior pituitary; in females it stimulates growth of the mammary glands and lactation after parturition
    crystal violet, gentian violet
    a green crystal (violet in water) used as a dye or stain or bactericide or fungicide or anthelmintic or burn treatment
    benzoyl peroxide
    a white crystalline peroxide used in bleaching (flour or oils or fats) and as a catalyst for free radical reactions
    active, active agent
    chemical agent capable of activity
    Alka-seltzer
    a commercial antacid that contains aspirin; tablets dissolve in water to give an effervescent solution
    Brioschi
    an antacid
    Bromo-seltzer
    an antacid
    Maalox
    an antacid
    Mylanta
    an antacid
    Prilosec, omeprazole
    antacid (trade name Prilosec) that suppresses acid secretion in the stomach
    Pepto-bismal
    an antacid
    Rolaids
    an antacid
    Tums
    an antacid
    reagent
    a chemical agent for use in chemical reactions
    desiccant, drier, drying agent, siccative
    a substance that promotes drying (e.g., calcium oxide absorbs water and is used to remove moisture)
    oxidant, oxidiser, oxidizer, oxidizing agent
    a substance that oxidizes another substance
    reducer, reducing agent, reductant
    a substance capable of bringing about the reduction of another substance as it itself is oxidized; used in photography to lessen the density of a negative or print by oxidizing some of the loose silver
    bleaching powder, chloride of lime, chlorinated lime
    a white powder comprised of calcium hydroxide and chloride and hypochlorite and used to bleach and/or disinfect
    calcium hypochlorite
    any hypochlorite of calcium; used as a bleaching agent
    cetrimide
    a cationic detergent that is a powerful disinfectant
    chlorine dioxide
    an explosive gas (ClO2) used chiefly in bleaching paper or starch or soap or flour and in water purification
    chlorine water
    an aqueous solution of chlorine used as a bleaching agent
    Clorox
    a commercial bleaching agent
    dimethylglyoxime
    a compound used in analysis as a precipitant for palladium or nickel
    VX gas
    a highly lethal nerve agent used in chemical warfare; a toxic liquid that penetrates the skin or lungs to disrupt the nervous system and stop respiration; in combat VX gas is deployed by detonating a container over the target area and can persist in the environment up to several weeks after release
    organophosphate nerve agent
    any of a series of nerve agents containing organophosphate compounds first synthesized by German chemists in 1936; in World War II the Germans tested them in concentration camps but not on the battlefield; Iraq is alleged to have used them against Iran and against the Kurds
    scavenger
    a chemical agent that is added to a chemical mixture to counteract the effects of impurities
    sodium hypochlorite
    an unstable salt (NaOCl) used as a bleaching agent and disinfectant
    surface-active agent, surfactant, wetter, wetting agent
    a chemical agent capable of reducing the surface tension of a liquid in which it is dissolved
    vesicant, vesicatory
    a chemical agent that causes blistering (especially mustard gas)
    type of:
    causal agency, causal agent, cause
    any entity that produces an effect or is responsible for events or results
    substance
    a particular kind or species of matter with uniform properties
  5. noun
    an active and efficient cause; capable of producing a certain effect
    “their research uncovered new disease agents
    see moresee less
    types:
    show 34 types...
    hide 34 types...
    pressor, vasoconstrictive, vasoconstrictor
    any agent that causes a narrowing of an opening of a blood vessel: cold or stress or nicotine or epinephrine or norepinephrine or angiotensin or vasopressin or certain drugs; maintains or increases blood pressure
    biohazard, biological agent
    any bacterium or virus or toxin that could be used in biological warfare
    eliminator
    an agent that eliminates something
    impairer
    an agent that impairs
    infectious agent, infective agent
    an agent capable of producing infection
    lethal agent
    an agent capable of causing death
    motor
    a nonspecific agent that imparts motion
    mutagen
    any agent (physical or environmental) that can induce a genetic mutation or can increase the rate of mutation
    enlivener, invigorator, quickener
    an agent that gives or restores life or vigor
    relaxer
    any agent that produces relaxation
    represser, repressor
    an agent that represses
    retardant, retardation, retardent
    any agent that retards or delays or hinders
    satisfier
    any agent capable of producing satisfaction
    shortener
    any agent that shortens
    stressor
    any agent that causes stress to an organism
    teratogen
    any agent that interferes with normal embryonic development: alcohol or thalidomide or X-rays or rubella are examples
    transmitter, vector
    any agent (person or animal or microorganism) that carries and transmits a disease
    weakener
    that which weakens or causes a loss of strength
    virus
    (virology) ultramicroscopic infectious agent that replicates itself only within cells of living hosts; many are pathogenic; a piece of nucleic acid (DNA or RNA) wrapped in a thin coat of protein
    pathogen
    any disease-producing agent (especially a virus or bacterium or other microorganism)
    adrenergic, adrenergic drug
    drug that has the effects of epinephrine
    Hypertensin, angiotensin, angiotonin
    any of several vasoconstrictor substances (trade name Hypertensin) that cause narrowing of blood vessels
    lypressin
    an antidiuretic and vasoconstrictor used to treat diabetes insipidus
    Privine, Sudafed, naphazoline
    vasoconstrictor (trade names Privine and Sudafed) used in nasal sprays to treat symptoms of nasal congestion and in eyedrops to treat eye irritation
    thalidomide
    a sedative and hypnotic drug; withdrawn from sale after discovered to cause severe birth defects because it inhibits angiogenesis
    vasopressor
    any agent that produces vasoconstriction and a rise in blood pressure (usually understood as increased arterial pressure)
    cold, coldness, frigidity, frigidness, low temperature
    the absence of heat
    noradrenaline, norepinephrine
    a catecholamine precursor of epinephrine that is secreted by the adrenal medulla and also released at synapses
    Adrenalin, adrenaline, epinephrin, epinephrine
    a catecholamine secreted by the adrenal medulla in response to stress (trade name Adrenalin); stimulates autonomic nerve action
    ADH, Pitressin, antidiuretic hormone, vasopressin
    hormone secreted by the posterior pituitary gland (trade name Pitressin) and also by nerve endings in the hypothalamus; affects blood pressure by stimulating capillary muscles and reduces urine flow by affecting reabsorption of water by kidney tubules
    obliterator
    an eliminator that does away with all traces
    gene delivery vector, transducing vector
    a vector for delivering genes into cells
    carrier, immune carrier
    (medicine) a person (or animal) who has some pathogen to which he is immune but who can pass it on to others
    nicotine
    an alkaloid poison that occurs in tobacco; used in medicine and as an insecticide
    type of:
    causal agency, causal agent, cause
    any entity that produces an effect or is responsible for events or results
  6. noun
    the semantic role of the animate entity that instigates or causes the happening denoted by the verb in the clause
    synonyms: agentive role
    see moresee less
    type of:
    participant role, semantic role
    (linguistics) the underlying relation that a constituent has with the main verb in a clause
Word Family
EDITOR’S CHOICE

Test prep from the experts

Boost your test score with programs developed by Vocabulary.com’s experts.

  • Proven methods: Learn faster, remember longer with our scientific approach.
  • Personalized plan: We customize your experience to maximize your learning.
  • Strategic studying: Focus on the words that are most crucial for success.

SAT/PSAT

$29.95
  • Number of words: 500+
  • Duration: 8 weeks or less
  • Time: 1 hour / week

TOEFL

$29.95
  • Number of words: 500+
  • Duration: 10 weeks or less
  • Time: 1 hour / week

ACT

$29.95
  • Number of words: 700+
  • Duration: 10 weeks
  • Time: 1 hour / week