nautical a buoy resembling a vertical log
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
How to use spar buoy in a sentence
A glance in the direction indicated showed the boys an object like a spar buoy apparently standing upright in the water.Boy Scouts in the North Sea | G. Harvey Ralphson
He had paid out nearly two miles of cord, when the top kite, a little two-footer, stood straight over the spar buoy in Newark Bay.
The spar buoy (fig. 50) may be adopted for situations where strong tides or currents prevail.
There's a black-and-red spar buoy there, as you see, but we haven't sighted it.The Adventure Club Afloat | Ralph Henry Barbour