敵わない[kanawanai] no match for
怨敵[onteki] sworn enemy
外敵[gaiteki] foreign enemy
敵う[kanau] to come true (wish)
仇敵[kyuuteki] bitter enemy

敵討[katakiuchi] vengeance
敵同士[tekidoushi] mutual enemies
旧敵[kyuuteki] old enemy
強敵[kyouteki] formidable enemy
公敵[kouteki] public enemy

し難い[shinikui] hard to do
一難[ichinan] one difficulty
火難[kanan] fire calamity
海難[kainan] shipwreck
患難[kannan] affliction

危難[kinan] peril
及び難い[oyobigatai] hard to attain to
救難[kyuunan] rescue
救難ヘリコプター[kyuunanherikoputaa] rescue helicopter
苦難[kunan] suffering