ない交ぜにする[naimazenisuru] to blend (e.g. truth and lies)
データ交換[deetakoukan] data exchange
メール交換[meerukoukan] exchange of letters
リーダー交代[riidaakoutai] leadership change
意見交換[ikenkoukan] exchange of ideas

一方交通[ippoukoutsuu] one-way traffic
羽交絞め[hagaijime] pinioning
仮名交じり[kanamajiri] mixed writing (characters and kana)
仮名交じり文[kanamajiribun] mixed writing (characters and kana)
賀詞交換[gashikoukan] New Year greetings (parties)

カード会員[kaadokaiin] (credit) card holder
ユダヤ教会堂[yudayakyoukaidou] synagogue
委員会[iinkai] committee
医会[ikai] medical society
医師会[ishikai] medical association

井戸端会議[idobatakaigi] content-free chat
育英会[ikueikai] scholarship society
一期一会[ichigoichie] once-in-a-lifetime encounter (hence should be cherished as such)
一般会計[ippankaikei] general accounting and finance
一般社会[ippanshakai] general public

哀歓[aikan] joys and sorrows
歓心を買う[kanshinwokau] to win favour
歓楽[kanraku] pleasure
歓楽街[kanrakugai] pleasure quarter
歓喜[kanki] delight

歓迎[kangei] welcome
歓迎会[kangeikai] welcome party
歓呼[kanko] acclamation
歓心[kanshin] favour
歓声[kansei] cheer