'time-waster' originates from English, formed as a compound of 'time' and 'waster', where 'time' ultimately comes from Old English 'tīma' meaning 'period, season' and 'waster' is derived from 'waste' + agent suffix '-er' (from Old North French and Latin roots).

'time' comes from Old English 'tīma'; 'waste' comes via Old North French 'waste' from Latin 'vastus' meaning 'empty, desolate'; the agent-forming suffix '-er' produced 'waster', and the modern compound 'time-waster' arose in Modern English by joining 'time' + 'waster'.

Initially, 'waste' could mean 'to lay waste' or 'make desolate'; over time it evolved to mean 'to use or expend carelessly', and 'time-waster' came to mean 'someone or something that causes time to be used unproductively'.