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

燕雀[enjaku] small birds
燕青拳[enseiken] Yangqingquan
燕巣[ensou] swift's nest (used to make bird's nest soup)
虎燕拳[koenken] Tiger Swallow Fist
燕支[enji] dark-red pigment

燕麦[enbaku] wild oat (Avena fatua)
飛燕[hien] swallow in flight
海燕[umitsubame] storm petrel (any bird of family Hydrobatidae)
燕千鳥[tsubamechidori] small Indian pratincole (bird) (Glareola lactea)