Denshi Jisho — Online Japanese dictionary

うなる to groan; to moan; to roar; to howl; to growl; to hum; to buzz; to sough
Godan verb with ru ending, Intransitive verb 
うめき a moan
Noun 
うめく to moan; to groan
Godan verb with ku ending, Intransitive verb, Usually written using kana alone 
しんぎん moaning; groaning
Noun, Suru verb 
き声 うめきごえ groan; moan; moaning
Noun 

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