un- + do

source: [冴えない彼女の育てかたの氷堂美智留がボタンを外すGIF画像｜無料GIF画像検索 GIFMAGAZINE 866539]

verb (undoes |-ˈdəz|, undoing; past undid; past participle undone) with object

1. unfasten, untie, or loosen (something):

〈ボタンなど〉をはずす; 〈ひも･結び目など〉をほどく, 緩める; 〈衣服など〉のボタンをはずす; 〈包みなど〉を開ける; 〈人〉の衣服のボタンをはずす

e.g. the knot was difficult to undo.

2. cancel or reverse the effects or results of (a previous action or measure):

〈なし終えたこと〉を元通りにする; 〈損害など〉を帳消しにする, 埋め合わせる; …を取り消す; 〈努力などの結果〉を台なしにする

e.g. there wasn't any way Evelyn could undo the damage.

cancel (the last one or more commands executed by a computer).

〘コンピュ〙 〈直前のコマンド〉を取り消す

3. formal cause the downfall or ruin of:

｟かたく｠ 〈人〉を破滅［零落］させる(→ undone)

e.g. Iago's hatred of women undoes him.

noun Computing

a feature of a computer program that allows a user to cancel or reverse the last one or more commands executed.

Old English undōn(see un-2, do1).