'dual-core' is a modern English compound of 'dual' and 'core'. 'dual' originates from Latin, specifically the word 'dualis' (from 'duo'), where 'duo' meant 'two'. 'core' originates from Old French, specifically the word 'coeur', where 'coeur' meant 'heart' (central part).

'dual' came into English via Latin 'dualis' (from 'duo') retaining the meaning 'two', while 'core' evolved from Old French 'coeur' into Middle English as 'core' meaning the central or innermost part. The compound 'dual-core' was coined in modern English (late 20th century) to describe processors with two cores.

Initially, 'dual' simply meant 'two' and 'core' meant 'heart' or 'central part'; over time the compound came to specifically mean 'having two processing cores (in a CPU)'.