約 やく Meanings Adverb approximately; about Noun promise; appointment; engagement shortening; reduction; simplification contraction (in phonetics) See also: 約音 (やくおん). Kanji 約 promise. Read as ヤク. Words containing 約 約束 (やくそく) promise 予約 (よやく) reservation 契約 (けいやく) contract And 381 more. Word lists JLPT N3 Jinuma: Japanese Dictionary · Word lists