'cross-question' is a Modern English compound formed from 'cross' + 'question'. 'Cross' in this sense comes from Old English 'cros' (ultimately from Latin 'crux') conveying opposition or across, and 'question' comes from Latin 'quaestio' (from 'quaerere', 'to ask, seek') via Old French and Middle English.

'cross-question' arose by analogy with compounds like 'cross-examine' in Modern English (from around the 17th–19th centuries), combining the sense of 'cross' (opposing, across) with 'question' to mean asking opposing or follow-up questions; it has remained a transparently compounded term to the present day.

Originally formed to express the idea of asking questions 'across' or in opposition to earlier statements, its meaning has largely remained stable and now denotes either the act of asking such questions (noun) or the act of performing them (verb).