'anti-streptococcus' originates from modern English, specifically the compound of the prefix 'anti-' and the noun 'streptococcus', where 'anti-' meant 'against' and 'streptococcus' refers to the bacterial genus 'Streptococcus'.

'streptococcus' comes from New Latin 'Streptococcus' (late 19th century), itself coined from Greek elements 'streptos' meaning 'twisted' and 'kokkos' meaning 'berry'; combining the prefix 'anti-' (from Greek 'anti', 'against') with 'streptococcus' produced the compound 'anti-streptococcus' in modern usage.

Initially formed transparently to mean 'against Streptococcus'; over time it has been used both as a descriptive adjective (e.g., anti-streptococcus activity) and as a noun name for agents (e.g., an anti-streptococcus serum).