Of a ship at a distance that the hull is visible above the horizon(adjective)
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Use "hull-up" in a sentence
"Without any control, the cruiser turned broadside to the wind and was rolled hull-up by a big wave."
"They had kept her hull-up until sunset, firing several shots after her, but the next morning she was nowhere to be seen."
"At length, when we had brought the chase fairly hull-up it became apparent that, thanks to the pains taken by the skipper to improve our rate of sailing, the _Eros_ was now a trifle the faster vessel of the two; and that, consequently, nothing short of an accident could prevent us from getting alongside the chase."