'waster' originates from Middle English, formed from the verb 'waste' plus the agent suffix '-er'. 'Waste' ultimately comes from Vulgar Latin 'vastare' (from Latin 'vastus') meaning 'empty' or 'desolate'.

'waster' developed after the verb 'waste' (from Old North French/Old French words derived from Latin 'vastare') was adopted into Middle English; the agent noun was created by adding the suffix '-er' to produce 'waster'.

Initially related to 'making desolate' or 'laying waste' (from Latin 'vastare'), the word 'waste' shifted toward 'using up or consuming carelessly', and 'waster' came to mean 'one who wastes' in the modern sense.