A tropical bird, Phaeton oethereus, often found far from land, whose cry resembles the whistle of a boatswain's pipe(noun)
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Use "boatswain-bird" in a sentence
"The name "boatswain-bird" is applied to some other kinds of birds, besides the tropic bird."
"It was not unbroken by sounds; but these were of a character to sadden rather than cheer them, for they were sounds to be heard only in the wilderness of the great deep, -- such as the half-screaming laugh of the sea-mew, and the wild whistle of the boatswain-bird."
"In that morning he says that a white bird was seen which has not the habit of sleeping on the sea, called _rabo de junco_ (boatswain-bird). ["