1545, "rejected as worthless," from L.L. reprobatus, pp. of reprobare "disapprove, reject, condemn," from L. re- "opposite of, reversal of previous condition" + probare "prove to be worthy" (see probate). The noun is recorded from 1545, "one rejected by God." Sense of "abandoned or unprincipled person" is from 1592. Earliest form of the word in Eng. was a verb, meaning "to disapprove" (1432).