'cross-examination' originates as an English compound of the words 'cross' and 'examination'. 'cross' traces back to Old English 'cros' (from Latin 'crux') meaning 'a cross' or 'transverse', and 'examination' comes from Latin 'examinatio' (from 'examinare') meaning 'a weighing, testing, inquiry'.

'cross' developed from Old English 'cros' (ultimately from Latin 'crux'), while 'examination' passed from Latin 'examinatio' into Old French (e.g. 'examen') and Middle English before becoming 'examination'. The compound 'cross-examination' arose in Early Modern English legal usage to denote questioning by the opposing party and became established in legal terminology.

Initially, the component words referred separately to 'cross' and to a general 'examination'; over time the compound narrowed to the specific legal sense 'questioning of a witness by the opposing side'.