Rare literary name for the lesser cuckoo (Cuculus poliocephalus), a bird associated with melancholy and transience in classical Japanese poetry. The common modern name is ホトトギス.
See also: ホトトギス
The mujōchō is a bird often composed about in old waka poetry.
From 無常 (mujō, 'impermanence') + 鳥 (chō, 'bird'), referring to the bird's call as a reminder of the transience of life in Buddhist-influenced classical poetry.