See Also: invalidate(medicine)
invalidate(dictionary)
invalidate(dictionary)

invalidate (iou)



invalidate verb trans. M17.
[medieval Latin invalidat- pa. ppl stem of invalidare invalidate, annul, formed as INVALID adjective1: see -ATE3. Perh. partly after French invalider.]
Make (an argument, contract, etc.) invalid; esp. deprive of legal efficacy.
J. Berman Freud's neurotic symptoms do not invalidate his psychological theories.
invali'dation noun L18.