永久歯[eikyuushi] permanent tooth
永久性[eikyuusei] permanency
永久脱毛[eikyuudatsumou] removing hair permanently
久しい[hisashii] long
久しく[hisashiku] for a long time

久し振りに[hisashiburini] after a long time
久し振り[hisashiburi] a long time (since the last time)
久懐[kyuukai] long-cherished hope
久慈目[kujime] spotbelly greenling (Hexagrammos agrammus)
久方[hisakata] sky

いい年をして[iitoshiwoshite] (in spite of) being old enough to know better
亥年[idoshi] year of the boar
一箇年[ikkanen] one year
一周年[isshuunen] one full year
一年以内に[ichineninaini] within a year

一年間[ichinenkan] (period of) one year
一年生[ichinensei] annual (plant)
一年草[ichinensou] annual (plant)
一年ぢゅう[ichinenjuu] all year round
一両年[ichiryounen] (a) year or two