Definitions

1. interjection

A sound, especially the call of a bird, such as a cockerel

“The farmer heard the ‘aau’ of a rooster in the early morning.”

2. noun

A loud, sharp cry or call

“The ‘aau’ of the crowd echoed through the stadium.”

3. verb

To make a loud, sharp cry or call

“The baby began to ‘aau’ loudly in its crib.”