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

隠密[onmitsu] privacy
過密[kamitsu] overcrowding
確率密度関数[kakuritsumitsudokansuu] probability density function
機密[kimitsu] secrecy
機密性[kimitsusei] confidentiality

機密保護[kimitsuhogo] security (e.g. data, password, etc.)
気密[kimitsu] airtight
気密室[kimitsushitsu] airtight chamber
緊密[kinmitsu] rigour
軍事秘密[gunjihimitsu] military secret