遺失[ishitsu] loss
遺失物[ishitsubutsu] lost article
一失[isshitsu] disadvantage (defect, error)
一得一失[ittokuisshitsu] gaining some and losing some
栄養失調[eiyoushicchou] malnutrition

過失[kashitsu] error
見失う[miushinau] to lose sight of
失う[ushinau] to lose
失する[shissuru] to lose
失せる[useru] to disappear

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