Definitions

1. verb

to make a loud, deep cry, especially of a cow or other animal, or to shout or cry out loudly

“The cow began to bellow in the distance, signaling the start of the parade.”

2. noun

a loud, deep cry, especially of a cow or other animal

“The sound of the bellow filled the entire valley.”

3. verb

to produce a loud, deep sound, especially of a horn or other instrument

“The trumpet began to bellow out the national anthem.”