'deaminative' originates from Modern English, specifically formed from the verb 'deaminate' plus the adjectival suffix '-ive', where the prefix 'de-' indicated 'removal' and 'amine' referred to an 'amine' (a nitrogen-containing organic group).

'deaminative' developed from 'deaminate' and 'deamination' (late 19th century formations). 'Deaminate' ultimately derives from 'amine' (coined in the mid-19th century from French 'amine', related to 'ammonia'), with 'de-' added to indicate removal and '-ive' to form an adjective.

Initially, the formation described the chemical action of removing an amino group; over time it has remained a technical term denoting the property or effect of causing deamination.