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

n a representative who acts on behalf of other persons or organizations

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Phineas Taylor Barnum
United States showman who popularized the circus (1810-1891)
William Frederick Cody
United States showman famous for his Wild West Show (1846-1917)
Sergei Pavlovich Diaghilev
Russian ballet impresario who founded the Russian ballet and later introduced it to the West (1872-1929)
Richard D'Oyly Carte
English impresario who brought Gilbert and Sullivan together and produced many of their operettas in London (1844-1901)
Solomon Hurok
United States impresario who was born in Russia (1888-1974)
Margarete Gertrud Zelle
Dutch dancer who was executed by the French as a German spy in World War I (1876-1917)
Charles Ringling
United States showman whose song-and-dance troop evolved into a circus (1863-1926)
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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
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
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
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
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
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
an undercover agent who is given no official cover
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
a special law-enforcement agent of the United States Treasury
someone appointed by a ruler as an administrative deputy
an operative who initiates his own defection (usually to a hostile country) for political asylum
Type of:
a person who represents others

n any agent or representative of a federal agency or bureau

federal agent
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
a federal agent who engages in trust busting
Type of:
functionary, official
a worker who holds or is invested with an office

n a businessperson who buys or sells for another in exchange for a commission

broker, factor
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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
an agent in the buying and selling of stocks and bonds
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
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

n a substance that exerts some force or effect

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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
a substance that is used as a medicine or narcotic
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)
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
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
any agent that promotes menstrual discharge
agent that induces milk secretion
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
an agent capable of activating specific genes
any agent that reduces milk secretion (as given to a woman who is not breast feeding)
any agent that enhances milk production
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
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
(biochemistry) a drug that can combine with a receptor on a cell to produce a physiological reaction
anaesthetic, anaesthetic agent, anesthetic, anesthetic agent
a drug that causes temporary loss of bodily sensations
a drug that neutralizes or counteracts the effects of another drug
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
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
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
trade name of a drug rich in iron; used to treat some kinds of anemia
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
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
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
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
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
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
hormone secreted by the isles of Langerhans in the pancreas; regulates storage of glycogen in the liver and accelerates oxidation of sugar in cells
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
a commercial antacid that contains aspirin; tablets dissolve in water to give an effervescent solution
an antacid
an antacid
an antacid
an antacid
Prilosec, omeprazole
antacid (trade name Prilosec) that suppresses acid secretion in the stomach
an antacid
an antacid
an antacid
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
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
a commercial bleaching agent
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
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
a particular kind or species of matter with uniform properties

n an active and efficient cause; capable of producing a certain effect

“their research uncovered new disease agents
Typhoid Mary
United States cook who was an immune carrier of typhoid fever and who infected dozens of people (1870-1938)
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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
an agent that eliminates something
an agent that impairs
infectious agent, infective agent
an agent capable of producing infection
lethal agent
an agent capable of causing death
a nonspecific agent that imparts motion
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
any agent that produces relaxation
represser, repressor
an agent that represses
retardant, retardation, retardent
any agent that retards or delays or hinders
any agent capable of producing satisfaction
any agent that shortens
any agent that causes stress to an organism
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
that which weakens or causes a loss of strength
(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
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
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
a sedative and hypnotic drug; withdrawn from sale after discovered to cause severe birth defects because it inhibits angiogenesis
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
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
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

n the semantic role of the animate entity that instigates or causes the happening denoted by the verb in the clause

agentive role
Type of:
participant role, semantic role
(linguistics) the underlying relation that a constituent has with the main verb in a clause

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