安全[anzen] safety
安全域[anzeniki] safety margin
安全運転[anzenunten] safe driving
安全器[anzenki] safety device
安全期[anzenki] safe period

安全教育[anzenkyouiku] safety education
安全性[anzensei] safety
安全対策[anzentaisaku] safety measure
安全第一[anzendaiichi] safety first
安全地帯[anzenchitai] safety zone

懐旧[kaikyuu] recalling the old days
旧ソ連[kyuusoren] former Soviet Union
旧悪[kyuuaku] past misdeeds
旧衣[kyuui] worn-out clothes
旧詠[kyuuei] ancient poems

旧怨[kyuuen] old grudge
旧縁[kyuuen] old relationship
旧恩[kyuuon] old favors
旧仮名遣[kyuukanazukai] former (i.e. before the post-WWII reforms) kana usage in writing the readings of kanji

愛書[aisho] great love of books
愛読書[aidokusho] favourite book
悪書[akusho] harmful book
案内書[annaisho] guidebook
移動図書館[idoutoshokan] mobile library

遺言書[yuigonsho] testament
遺書[isho] note left by dead person
医書[isho] medical book
一つ書き[hitotsugaki] an item
一書[issho] one letter

安全保障条約[anzenhoshoujouyaku] US-Japan Security Treaty
違約[iyaku] breach of contract
違約金[iyakukin] penalty for contract breach
一粒子既約[ichiryuushikiyaku] one particle irreducible (physics)
化学兵器禁止条約[kagakuheikikinshijouyaku] chemical weapons ban treaty

仮条約[karijouyaku] provisional treaty
会う約束[auyakusoku] rendezvous
会員規約[kaiinkiyaku] membership agreement (e.g. for a credit card)
解約[kaiyaku] cancellation of contract
確約[kakuyaku] firm promise