'larvicide' originates from Neo-Latin/Latin formation, specifically the component 'larva' and the Latin verb 'caedere', where 'larva' originally meant 'mask; ghost' (later used in biology for a 'young form') and 'caedere' meant 'to kill'.

'larvicide' was formed in modern scientific/Neo-Latin usage by combining 'larva' + the suffix '-cide' (from Latin 'caedere'), and entered English usage in the 20th century as 'larvicide' (plural 'larvicides').

Initially coined to denote an agent that kills larval forms of organisms, it has retained that specific meaning in modern usage as 'a substance that kills larvae', especially insect larvae such as mosquitoes.