一利一害[ichiriichigai] advantages and disadvantages
煙害[engai] smoke pollution
加害[kagai] assault
加害者[kagaisha] assailant
禍害[kagai] evil

害悪[gaiaku] harm
害虫[gaichuu] harmful insect
害鳥[gaichou] vermin
害毒[gaidoku] harm

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

満更夢ではない[manzarayumedehanai] not altogether a dream
一更[ikkou] first watch
五更[gokou] the five night watches
更かす[fukasu] to sit up late
更ける[fukeru] to get late

更なり[saranari] of course
更に[sarani] furthermore
更位[koui] second accession of the same emperor
更衣室[kouishitsu] locker room
更改[koukai] renewal

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

エンジン故障[enjinkoshou] engine failure
安全保障[anzenhoshou] security guarantee (e.g. military security, network security, etc.)
安全保障条約[anzenhoshoujouyaku] US-Japan Security Treaty
画障[gashou] pictured paper doors
気に障る[kinisawaru] to hurt one's feelings

気障[kiza] affected
血行障害[kekkoushougai] disturbance (blockage) of blood flow
故障[koshou] break-down
黒内障[kokunaishou] black cataract
差し障り[sashisawari] offence