Frog's sound

CROAK

Think of the deep, raspy call a bullfrog makes at night by the pond—it’s not a chirp or a ribbit.

The clue "Frog's sound" is a straightforward definition pointing to the noise frogs make. "Croak" is the onomatopoeic word for that deep, raspy call you’d hear from a frog, especially at night. There’s no hidden wordplay here—it’s a direct match between the clue and the answer. If you’ve ever heard a frog, you’d recognize the sound instantly.