Denshi Jisho — Online Japanese dictionary

約束 やくそく 1: arrangement; promise; appointment; pact; engagement;
2: convention; rule
Common word, Noun, Suru verb 
約束事 やくそくごと 1: promise; vow; engagement;
2: convention; rule; resolution
Noun 
約束の地 やくそくのち Promised Land
Noun 
約束通り やくそくどおり as one promised
Common word, Noun, Adverb 
約束手形 やくそくてがた promissory note
Noun 
約束破る やくそくやぶる to break a promise; to go back on one's word; to renege
Expression, Godan verb with ru ending 
約束どおり やくそくどおり as one promised
Noun, Adverb 
約束やぶる やくそくやぶる to break a promise; to go back on one's word; to renege
Expression, Godan verb with ru ending 
約束に背く やくそくにそむく to break one's promise
Expression, Godan verb with ku ending 
約束の通り やくそくのとおり as promised; true to one's promise
Noun 
約束を守る やくそくをまもる to keep a promise; to keep one's word
Expression, Godan verb with ru ending 
約束を破る やくそくをやぶる to break a promise; to go back on one's word; to renege
Expression, Godan verb with ru ending 
約束をやぶる やくそくをやぶる to break a promise; to go back on one's word; to renege
Expression, Godan verb with ru ending 

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