noun
mute swan
A species of swan with a distinctive black knob on the orange bill. Scientific name: Cygnus olor.
公園の池にコブハクチョウがいる。
There is a mute swan in the park pond.
Compound of 瘤 (こぶ, 'bump, knob') + 白鳥 (はくちょう, 'swan'), referring to the prominent black knob at the base of the bill.