Meaning

verb cancel, annul, or reverse an action or its effect

verb deprive of certain characteristics

verb cause the ruin or downfall of

originFrom Middle English undōn, from Old English ondōn, from Proto-West Germanic *andadōn (“to undo”), equivalent to un- + do. Cognate with West Frisian ûndwaan, ûntdwaan (“to undo; rid”), Dutch ontdoen (“to undo”).

Etymology from Wiktionary, CC BY-SA 3.0