Available Definitions:
1) v. i. - To make a low, hoarse noise in the throat, as a frog, a raven, or a crow; hence, to make any hoarse, dismal sound.
2) v. i. - To complain; especially, to grumble; to forebode evil; to utter complaints or forebodings habitually.
3) v. t. - To utter in a low, hoarse voice; to announce by croaking; to forebode; as, to croak disaster.
4) n. - The coarse, harsh sound uttered by a frog or a raven, or a like sound.