営巣[eisou] building a nest
炎症病巣[enshoubyousou] inflamed part
燕巣[ensou] swift's nest (used to make bird's nest soup)
帰巣性[kisousei] homing instinct
空巣狙い[akisunerai] prowler

古巣[furusu] old haunts
精巣[seisou] testicle
青懸巣[aokakesu] blue jay (Cyanocitta cristata)
鼠巣[sosou] rat's nest

鴉片窟[ahenkutsu] opium den
仙窟[senkutsu] enchanted cave
巣窟[soukutsu] den
洞窟[doukutsu] cave
貧民窟[hinminkutsu] slums

魔窟[makutsu] den of thieves
偏窟[henkutsu] eccentricity
理窟[rikutsu] theory
巌窟[gankutsu] cave