'backhander' originates from English, specifically the compound 'backhand' with the agentive suffix '-er', where 'back' meant 'back', 'hand' meant 'hand', and '-er' denoted 'one who performs an action'.

'backhand' originally appeared as the phrase 'back hand' meaning a strike with the back of the hand; by the late 19th century it became established as the sports term 'backhand' (a tennis/racquet stroke), and the form 'backhander' developed to mean the stroke. In 20th-century British informal usage the term was extended metaphorically to mean a 'bribe'.

Initially it meant 'a strike with the back of the hand' or 'a tennis stroke', but over time in colloquial British English it evolved to include the figurative meaning 'a bribe' (an under-the-table payment).