'debunk' originates from the English word 'bunk', which was a slang term for 'nonsense'. The prefix 'de-' was added to indicate removal or reversal.

'bunk' was used in American English in the early 20th century, and 'debunk' emerged as a term to describe the act of exposing 'bunk'.

Initially, it meant 'to remove nonsense', and this meaning has largely remained the same in modern usage.