'flower-averse' originates from Modern English, composed of the noun 'flower' and the adjective 'averse'; 'flower' ultimately comes from Old English 'flōwer' (and Middle English 'flour') referring to the bloom of a plant, and 'averse' originates from Latin 'aversus' (past participle of 'avertere').

'flower' developed from Old English 'flōwer' (via Middle English 'flour') from Proto-Germanic roots meaning 'blossom'; 'averse' changed from Latin 'aversus' (from 'avertere', 'to turn away') through Old French/Medieval Latin forms into Middle English 'averse' and finally the modern English adjective 'averse'. The compound 'flower-averse' is a relatively recent, transparent Modern English coinage combining these elements.

The components originally referred separately to 'a plant's bloom' and 'turned away'; combined in modern usage the compound now means 'turned away from flowers' i.e. 'having a dislike of flowers'.