noun
Pharmacological term for an antibiotic agent; used in medical and pharmaceutical contexts.
この抗生剤は細菌感染に効果がある。
This antibiotic is effective against bacterial infections.
抗生物質 is the more common general term for 'antibiotic', while 抗生剤 is a technical pharmacological term often used in medical prescriptions and drug classifications.
Compound of 抗 (こう, 'anti-') + 生 (せい, 'life' or 'living organism') + 剤 (ざい, 'agent' or 'medicine'), literally 'anti-life agent', referring to a substance that acts against microorganisms.