'time-sink' originates from Modern English, specifically the words 'time' + 'sink', where 'time' derives from Old English 'tīma' meaning 'time, season' and 'sink' comes from Old English 'sincan' (verb) meaning 'to sink'.

'time' changed from Old English 'tīma' into the modern English 'time'; 'sink' evolved from Old English 'sincan' (verb) and related nouns; the compound metaphorical use 'time-sink' emerged in late 20th-century English (notably computing and gaming contexts) and became the modern English compound 'time-sink'.

Initially, 'sink' was used in literal senses (to sink, or a receptacle); over time it acquired metaphorical uses as a 'receiver' or 'consumer' of resources, and 'time-sink' came to mean something that 'absorbs' or 'consumes' time, often with little productive return.