'acerber' 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 'acerber'.

Initially, it meant 'sharp or bitter in taste', but over time it evolved into its current meaning of 'having a more bitter or harsh quality'.