Denshi Jisho — Online Japanese dictionary

ため息 ためいき sigh
Common word, Noun 
ため息をつく ためいきをつく to sigh; to breathe a sigh
Expression, Godan verb with ku ending 
ため息を吐く ためいきをつく to sigh; to breathe a sigh
Expression, Godan verb with ku ending 

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