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

安全期[anzenki] safe period
暗黒期[ankokuki] eclipse period
一期[ichigo] one's life time
一期[ikki] one term
一期一会[ichigoichie] once-in-a-lifetime encounter (hence should be cherished as such)

一周期[isshuuki] period (in astronomy)
一定期間[itteikikan] fixed interval
延期[enki] postponement
延期になる[enkininaru] to be postponed
沖積期[chuusekiki] alluvial period

老麺[raamen] ramen (Chinese-style noodles)
家老[karou] chief retainer
棄老[kirou] old person thrown away in the mountains
敬老[keirou] respect for the aged
敬老の日[keirounohi] Respect-for-the-Aged Day Holiday (third Monday in September)

元老[genrou] elder statesman
元老院[genrouin] (Roman) senate
故老[korou] old people
車海老[kurumaebi] kuruma prawn (Marsupenaeus japonicus)
寿老人[juroujin] god of longevity