'antibiotic' originates from Greek and New Latin elements: 'anti-' meaning 'against' and 'biotic' from Greek 'bios' meaning 'life'; the adverb 'antibiotically' is formed by adding the adjective-forming suffix '-ic' and the adverbial suffix '-ally'.

'antibiotic' developed from the Greek-derived compound 'antibiosis' (late 19th century) and New Latin 'antibioticus'; it entered English as 'antibiotic' in the early 20th century and later formed the adverb 'antibiotically'.

Initially related to the general idea of being 'against life' or 'opposing living organisms' (in the compound sense); over time it became specialized to mean substances that inhibit or kill bacteria, and 'antibiotically' now usually means 'by or in the manner of antibiotics'.