Something that's antibacterial works by killing bacteria or keeping it from growing. You might put antibacterial ointment on a cut to help keep it clean and free from infection.

Officially, an antibiotic like penicillin is an antibacterial agent — it kills bacteria, microorganisms that cause disease. You're more likely to find the word antibacterial describing special soaps and lotions that don't just wash bacteria off your hands, but actually kill them. The word combines anti-, "against," and bacterial, from the Greek root bakterion, "small staff," which describes the shape of the first bacteria seen through microscopes.

Definitions of antibacterial
  1. adjective
    destroying bacteria or inhibiting their growth
  2. noun
    any drug that destroys bacteria or inhibits their growth
    synonyms: antibacterial drug, bactericide
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    antibiotic, antibiotic drug
    a chemical substance derivable from a mold or bacterium that can kill microorganisms and cure bacterial infections
    Zithromax, azithromycin
    a systemic antibacterial medicine (trade name Zithromax) that is prescribed to treat bacterial infections in many different parts of the body
    antibacterial drug used to treat leprosy and some kinds of skin diseases
    Dynapen, dicloxacillin
    antibacterial (trade name Dynapen) used to treat staphylococcal infections that are resistant to penicillin
    antibacterial substance that is a water-soluble powder used in antiseptic soaps and toothpaste
    INH, Nydrazid, isoniazid
    antibacterial drug (trade name Nydrazid) used to treat tuberculosis
    Mandelamine, Urex, methenamine
    antibacterial agent (trade names Mandelamine and Urex) that is contained in many products that are used to treat urinary infections
    NegGram, nalidixic acid
    antibacterial agent used especially to treat genitourinary infections
    trade name for a topical drug containing several antibacterials; used as an ointment for skin irritations and in the form of eyedrops for minor eye infections
    Macrodantin, nitrofurantoin
    derivative of nitrofuran used as an antibacterial medicine (trade name Macrodantin) effective against a broad range of Gram-positive and Gram-negative bacteria; used to treat infections of the urinary tract
    Rifadin, Rimactane, rifampin
    an antibacterial drug (trade names Rifadin and Rimactane) used to treat tuberculosis
    sulfa, sulfa drug, sulfonamide, sulpha
    antibacterial consisting of any of several synthetic organic compounds capable of inhibiting the growth of bacteria that require PABA
    Achromycin, tetracycline
    an antibiotic (trade name Achromycin) derived from microorganisms of the genus Streptomyces and used broadly to treat infections
    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
    any of various red antibiotics isolated from soil bacteria
    an antibiotic and antifungal agent
    a crystalline antibiotic active against various fungi
    antineoplastic antibiotic
    an antibiotic drug used as an antineoplastic in chemotherapy
    Azactam, aztreonam
    an antibiotic (trade name Azactam) used against severe infections; has minimal side effects
    a polypeptide antibiotic of known chemical structure effective against several types of Gram-positive organisms; usually applied locally
    a colorless basic antibiotic that inhibits the growth of Gram-positive organisms
    Kafocin, cephaloglycin
    antibiotic related to cephalosporin but no longer in common use
    a broad spectrum semisynthetic antibiotic produced by modifying cephalosporin
    Mefoxin, cephalosporin
    one of several broad spectrum antibiotic substances obtained from fungi and related to penicillin (trade names Mefoxin); addition of side chains has produced semisynthetic antibiotics with greater antibacterial activity
    Chloromycetin, chloramphenicol
    an oral antibiotic (trade name Chloromycetin) used to treat serious infections (especially typhoid fever)
    Aureomycin, chlortetracycline
    a yellow crystalline antibiotic (trade name Aureomycin) used to treat certain bacterial and rickettsial diseases
    Cipro, ciprofloxacin
    an oral antibiotic (trade name Cipro) used against serious bacterial infections of the skin or respiratory tract or urinary tract or bones or joints
    an antibiotic that is especially active against the tubercle bacillus
    Declomycin, demeclocycline hydrochloride
    tetracycline antibacterial (trade name Declomycin) effective in the treatment of some bacterial and rickettsial and other infections
    antibiotic consisting of a hydrogenated form of streptomycin; used against tuberculosis and tularemia and Gram-negative organisms
    an antibiotic used as an anticancer drug
    Vibramycin, doxycycline
    an antibiotic derived from tetracycline that is effective against many infections
    E-Mycin, Erythrocin, Ethril, Ilosone, Pediamycin, erythromycin
    an antibiotic (trade name Erythrocin or E-Mycin or Ethril or Ilosone or Pediamycin) obtained from the actinomycete Streptomyces erythreus; effective against many Gram-positive bacteria and some Gram-negative
    Garamycin, gentamicin
    an antibiotic (trade name Garamycin) that is derived from an actinomycete; used in treating infections of the urinary tract
    an antibiotic produced by a soil bacterium; used chiefly as an antiseptic in treating local infections produced by Gram-positive bacteria
    Kantrex, kanamycin
    antibiotic (trade name Kantrex) used to treat severe infections
    Lincocin, lincomycin
    antibiotic (trade name Lincocin) obtained from a streptomyces bacterium and used in the treatment of certain penicillin-resistant infections
    Minocin, minocycline
    tetracycline antibiotic (trade name Minocin) used to treat a variety of bacterial and rickettsial infections
    Mutamycin, mitomycin
    a complex of antibiotic substances obtained from a streptomyces bacterium; one form (trade name Mutamycin) shows promise as an anticancer drug
    a highly unsaturated antibiotic acid obtained from an actinomycete
    Neobiotic, fradicin, neomycin
    an antibiotic obtained from an actinomycete and used (as a sulphate under the trade name Neobiotic) as an intestinal antiseptic in surgery
    an antibiotic obtained from an actinomycete and used to treat infections by Gram-positive bacteria
    Mycostatin, Nystan, nystatin
    an antifungal and antibiotic (trade names Mycostatin and Nystan) discovered in New York State; derived from soil fungi actinomycetes
    Terramycin, hydroxytetracycline, oxytetracycline, oxytetracycline hydrochloride
    a yellow crystalline antibiotic (trademark Terramycin) obtained from a soil actinomycete; used to treat various bacterial and rickettsial infections
    any of various antibiotics obtained from Penicillium molds (or produced synthetically) and used in the treatment of various infections and diseases
    any of several toxic antibiotics obtained from a particular soil bacterium
    trade name for a parenteral antibiotic
    a yellow-green mixture of antibiotics obtained from the bacillus of green pus
    a toxic blue crystalline antibiotic found in green pus
    an antibiotic used to treat gonorrhea
    an antibiotic produced by the actinomycete Streptomyces griseus and used to treat tuberculosis
    a basic antibiotic derived from a soil actinomycete
    a polypeptide antibiotic (similar to bacitracin) obtained from a soil bacterium
    Sulamyd, sulfacetamide
    a topical sulfonamide (trade name Sulamyd) used to treat eye infections
    a sulfa drug used in treating meningitis and pneumonia and other infections
    sulfamethazine, sulfamezathine
    a sulfa drug used like sulfadiazine and also in veterinary medicine
    Gantanol, sulfamethoxazole
    a sulfonamide (trade name Gantanol) used to treat infections (especially infections of the urinary tract)
    a white odorless crystalline sulfa drug; the parent compound of most of the sulfa drugs
    sulfa drug derived from pyridine and sulfanilamide
    Gantrisin, sulfisoxazole
    a sulfonamide (trade name Gantrisin) used to treat infections of the urinary tract
    trade name for a sulfonamide antibacterial
    Nebcin, tobramycin
    an antibiotic (trade name Nebcin) that is especially effective against Gram-negative bacteria
    tyrocidin, tyrocidine
    a basic polypeptide antibiotic derived from a soil bacterium; a major component of tyrothricin
    a mixture of antibiotics applied locally to infections caused by Gram-positive bacteria
    Vancocin, vancomycin
    an antibiotic (trade name Vancocin) effective against some bacterial infections
    Viocin, viomycin
    a basic polypeptide antibiotic (trade name Viocin) administered intramuscularly (along with other drugs) in the treatment of tuberculosis
    type of:
    medicament, medication, medicinal drug, medicine
    (medicine) something that treats or prevents or alleviates the symptoms of disease
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