Cuttle bone

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Cut´tle bone`

1.The shell or bone of cuttlefishes, used for various purposes, as for making polishing powder, etc.
Webster's Revised Unabridged Dictionary, published 1913 by G. & C. Merriam Co.
References in periodicals archive ?
Daily wear is needed to keep thebird's beak and its claws the proper length, so be sure to provide a salt block or a cuttle bone for the bird to chew on.