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lesser cuckoo (Cuculus poliocephalus)
「子規」 has another reading with different meanings.
夏になると時鳥の鳴き声が聞こえる。
When summer arrives, the cry of the lesser cuckoo can be heard.
夜明けに目を覚ますと時鳥が鳴いていた。
When I woke up at dawn, the lesser cuckoo was calling.
俳句では時鳥は夏の季語として親しまれている。
In haiku, the lesser cuckoo is well loved as a summer seasonal word.