Denshi Jisho — Online Japanese dictionary

籠もる こもる 1: (Usually written using kana alone) to seclude oneself; to be confined in;
2: to be filled (e.g. with emotion, satire, etc.); to be heavy (with);
3: to be stuffy;
4: to be implied
Common word, Godan verb with ru ending, Intransitive verb 

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