Denshi Jisho — Online Japanese dictionary

群れ むれ group; crowd; flock; herd; bevy; school; swarm; cluster (e.g. of stars); clump; pack (e.g. of dogs)
Common word, Noun 
群れる むれる to crowd; to flock; to swarm
Common word, Ichidan verb, Intransitive verb 
群れ居る むれいる to crowd in; to come together
Ichidan verb, Intransitive verb 
群れ遊ぶ むれあそぶ to play in a group
Godan verb with bu ending 
群れを成す むれをなす to form groups
Expression, Godan verb with su ending 
群れ集まる むれあつまる to gather in large groups
Godan verb with ru ending 

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