Denshi Jisho — Online Japanese dictionary

一生 いっしょう 1: whole life; a lifetime; all through life; one existence; a generation; an age; the whole world; the era;
2: (No-adjective) (the only, the greatest, etc.) of one's life
Common word, Adverbial noun, Temporal noun, No-adjective 
一生面 いちせいめん innovation; new vista or field
Noun 
一生面 いっせいめん innovation; new vista or field
Noun 
一生涯 いっしょうがい lifetime; one's whole life; all through life
Temporal noun 
一生物 いっしょうもの item that will last a lifetime
Noun, No-adjective 
一生もの いっしょうもの item that will last a lifetime
Noun, No-adjective 
一生不犯 いっしょうふぼん (strict) observance of the Buddhist precept of lifelong celibacy
Noun 
一生懸命 いっしょうけんめい very hard; with utmost effort; with all one's might; for dear life
Common word, Na-adjective, Adverbial noun, Noun 
一生けん命 いっしょうけんめい very hard; with utmost effort; with all one's might; for dear life
Na-adjective, Adverbial noun, Noun 

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