'twin-core' originates from Modern English compound of the words 'twin' and 'core', where 'twin' meant 'paired' or 'twofold' and 'core' meant 'central part' or 'kernel' (applied to a processor core in computing).

'twin' goes back to Old English 'twin(n)' (from Proto-Germanic *twi- / 'twofold'), while 'core' comes via Old French from Latin 'cor' (originally 'heart') and Middle English 'core' meaning 'central part'; the compound 'twin-core' formed in modern technical English to denote a component with two cores.

Initially the elements referred generally to 'a paired central part'; in computing the compound evolved to mean specifically 'a processor configuration with two processing cores'.