'anticontagiousness' originates from Greek and Latin-derived English components: the prefix 'anti-' (from Greek 'antí') meaning 'against' and the adjective 'contagious' (from Latin 'contagiosus' via Old French), combined with the noun-forming suffix '-ness'.

'anti-' comes from Greek 'antí' meaning 'against'; 'contagious' comes from Latin 'contagiosus' (from 'contagium'/'contagere' meaning 'touching' or 'contact') and passed into Old French (e.g. 'contagieux') and Middle English as 'contagious'; in modern English these elements were compounded to form the nonce/technical noun 'anticontagiousness'.

Initially the components conveyed 'against contagion' (anti- + contagious), and as a compound the word has come to mean 'the state or quality of not being contagious.'