Denshi Jisho — Online Japanese dictionary

休む やすむ 1: to be absent; to take a day off;
2: to rest; to have a break;
3: to go to bed; to (lie down to) sleep; to turn in; to retire;
4: to stop doing some ongoing activity for a time; to suspend business
Common word, Godan verb with mu ending, Intransitive verb 

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