'applaudable' originates from Latin, specifically the word 'applaudere', where 'ad-' meant 'to' and 'plaudere' meant 'to clap'. The suffix '-able' comes from Latin '-abilis' (via Old French), meaning 'able to be'.

'applaudable' changed from Latin 'applaudere' through Old French 'applaudir' and Middle English 'applauden', and eventually became the modern English adjective 'applaudable' by adding the suffix '-able'.

Initially, it meant 'to clap; to express approval by clapping', but over time it evolved into its current adjectival meaning of 'worthy of applause or praise'.