The baaa sound from a sheep is called bleating: The sheep is bleating. To bleat is a characteristic wavering cry, such as a baaaa.

Bleating is the name for when a sheep says "Baa". Just like barking is the same for when a dog says "woof". :)

"Bleat" is the sound it makes https://www.google.com/search?q=bleat+meaning&oq=bleat+meaning&aqs=chrome..69i57j0l9.3401j1j7&sourceid=chrome&ie=UTF-8

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