'acerb' originates from Latin, specifically the word 'acerbus,' where 'acer-' meant 'sharp' or 'bitter.'

'acerbus' transformed into the Old French word 'acerbe,' and eventually became the modern English word 'acerb' through Middle English.

Initially, it meant 'sharp or bitter in taste,' but over time it evolved into its current meaning of 'sharp or biting in character or tone.'