偉功[ikou] great deed
遺功[ikou] works following the deceased
気功[kikou] breathing exercise
九仞の功[kyuujinnokou] spectacular success
勲功[kunkou] merits

軍功[gunkou] meritorious war service
蛍雪の功[keisetsunokou] the fruit of diligent study
功業[kougyou] exploit
功罪[kouzai] both good and bad
功績[kouseki] achievements

コスト効率[kosutokouritsu] cost effectiveness
圧電効果[atsudenkouka] piezoelectric effect
偉効[ikou] great effect
逆効果[gyakukouka] backfire
経済効果[keizaikouka] (positive) economic effect

効果[kouka] effect
効果音[koukaon] sound effect
効果的[koukateki] effective
効果覿面[koukatekimen] bring an immediate result on

一触即発[isshokusokuhatsu] critical (touch and go) situation
即く[tsuku] to ascend (the throne)
即ける[tsukeru] to install (a king, emperor, etc.)
色即是空[shikisokuzekuu] form is emptiness
即する[sokusuru] to conform to

即ち[sunawachi] that is
即位[sokui] enthronement
即応[sokuou] compliance
即興[sokkyou] improvisation
即興曲[sokkyoukyoku] impromptu (musical)