What does "croak" mean?

Croak: To complain; especially, to grumble; to forebode evil; to utter complaints or forebodings habitually. Marat . . . croaks with reasonableness. Carlyle.

Additional senses

  1. 2.To utter in a low, hoarse voice; to announce by croaking; to forebode; as, to croak disaster. The raven himself is hoarse, That croaks the fatal entrance of Duncan. Shak. Two ravens now began to croak Their nuptial song. Wordsworth.
  2. 3.The coarse, harsh sound uttered by a frog or a raven, or a like sound.

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