Wiktionary
dan buoy
n. (context nautical English) A small buoy, sometimes made of cork with a small flag, used to temporarily mark a position at sea, normally to mark a fishing ground, a minesweeping area, or a man overboard.
Usage examples of "dan buoy".
Haley found himself curiously short of breath although the distance from the stern to the bridge had not called for any undue exertion _ Booth nodded towards a beflagged dan buoy which swung and bobbed a little way ahead.
It was dark now, a cold breeze fluttering the flag of a dan buoy, all the nets neatly stowed along the inside of the bulwarks.
I got to the first shoal all right and the slender stick of the dan buoy slid past the bows, illumined in a triple flash of lightning.