To cross-examine is to question a witness for the opposite side in a court trial or someone who might have adverse interests to yours.(verb)
When you are a defendant and ask repeated questions in court of a person testifying against you, this is an example of a situation where you cross-examine.
See cross-examine in Webster's New World College Dictionary
See cross-examine in American Heritage Dictionary 4
verb cross-ex·am·ined, cross-ex·am·in·ing, cross-ex·am·ines verb, transitive
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