Denshi Jisho — Online Japanese dictionary

遊ぶ あそぶ 1: to play; to enjoy oneself; to have a good time;
2: to mess about (with alcohol, gambling, philandery, etc.);
3: to be idle; to do nothing; to be unused;
4: to go to (for pleasure or for study);
5: (in baseball) to intentionally throw a ball to lower the batter's concentration
Common word, Godan verb with bu ending, Intransitive verb 
遊ぶ あすぶ 1: to play; to enjoy oneself; to have a good time;
2: to mess about (with alcohol, gambling, philandery, etc.);
3: to be idle; to do nothing; to be unused;
4: to go to (for pleasure or for study);
5: (in baseball) to intentionally throw a ball to lower the batter's concentration
Out-dated or obsolete kana, Godan verb with bu ending, Intransitive verb 
遊ぶ すさぶ to grow wild; to rage; to become rough
Godan verb with bu ending, Intransitive verb 

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