Denshi Jisho — Online Japanese dictionary

一緒に いっしょに together (with); at the same time; in a lump
Common word, Adverb 
一緒にする いっしょにする 1: to unite; to join; to do together;
2: to confuse with
Expression, Suru verb - irregular 
一緒になる いっしょになる to come together; to join
Expression, Godan verb with ru ending 

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