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

横恋慕[yokorenbo] illicit love
失恋[shitsuren] disappointed love
はつ恋[hatsukoi] first love
色恋[irokoi] sensual love
道ならぬ恋[michinaranukoi] illicit love affair

悲恋[hiren] blighted love
恋い初める[koisomeru] to begin to love
恋い忍ぶ[koishinobu] to live on love
恋慕う[koishitau] to miss