'uneven-leaved' originates from Modern English; it is a compound of 'uneven' and the adjective-forming element '-leaved' derived from 'leaf'. 'uneven' itself comes from the prefix 'un-' plus 'even', and '-leaved' comes from 'leaf' with a past-participle/adjectival formation.

'uneven' developed from Old English elements: the negative prefix 'un-' combined with 'efen/ēfen' (Old English for 'level' or 'even'); 'leaf' comes from Old English 'lēaf'. These elements combined in later English to form compounds such as 'uneven-leaved'.

Initially the components referred separately to 'not even' and 'leaf'; over time the compound came to specifically describe plants whose leaves are unequal in size, shape, or arrangement.