'antisensitizer' is a compound formed in modern English from the prefix 'anti-' and the noun 'sensitizer.' 'anti-' originates from Greek 'anti-' meaning 'against' and 'sensitizer' comes from the verb 'sensitize' (see below).

'sensitize' comes into English via Modern French 'sensibiliser' and Late Latin 'sensibilis' meaning 'perceptible' or 'sensible'; the agent-forming suffix '-izer' (from French/English) produced 'sensitizer,' and 'anti-' was prefixed to form 'antisensitizer' in technical usage.

Originally related to 'sensible' meaning 'able to perceive,' the root developed into 'sensitize' meaning 'to make sensitive'; 'antisensitizer' thus evolved to mean 'an agent against sensitization' in modern technical contexts.