Denshi Jisho — Online Japanese dictionary

やく 1: approximately; about;
2: (Noun) promise;
3: shortening; reduction; simplification;
4: (Linguistic term) contraction (in phonetics)
Common word, Adverb 
きやく agreement; rules; code; protocol; convention
Common word, Noun 
よやく 1: reservation; appointment; booking; advance order;
2: contract; subscription; pledge
Common word, Noun, Suru verb, No-adjective 
いやく breach of contract; default
Noun, Suru verb 
きやく irreducible
Na-adjective, Noun, No-adjective 
きやく breaking a promise
Noun 
はやく breach of contract; breaking of word
Noun, Suru verb 
ひやく reduced
Na-adjective, Mathematical term 
やくて promissory note
Noun 
かいやく cancellation of contract
Common word, Noun, Suru verb 
かくやく firm promise; definite promise
Common word, Noun, Suru verb 
けいやく contract; compact; agreement
Common word, Noun, Suru verb 
けんやく thrift; economy; frugality
Common word, Na-adjective, Noun, Suru verb, No-adjective 
こうやく public commitment or promise
Common word, Noun, Suru verb, No-adjective 
こんやく engagement; betrothal
Common word, Noun, Suru verb, No-adjective 
せいやく limitation; restriction; condition; constraints
Common word, Noun, Suru verb 
せいやく conclusion of a contract
Common word, Noun, Suru verb 
せいやく written vow; pledge; covenant
Common word, Noun, Suru verb 
せつやく economising; saving
Common word, Noun, Suru verb 
ていやく conclusion of a treaty
Common word, Noun, Suru verb 
とくやく special contract; special agreement; rider (insurance)
Common word, Noun, Suru verb 
みつやく secret agreement
Common word, Noun, Suru verb 
めいやく oath; pledge; pact; covenant
Common word, Noun, Suru verb 
やくそく 1: arrangement; promise; appointment; pact; engagement;
2: convention; rule
Common word, Noun, Suru verb 
やっかん agreement; stipulation; article; clause
Common word, Noun 
ようやく summary; digest
Common word, Noun, Suru verb, No-adjective 
かんやく conciseness; brevity; simplification
Na-adjective, Noun, No-adjective 

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