a freestanding circular stone belfry built in Ireland from the 10th century beside a monastery and used as a place of refuge
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
Examples from the Web for round tower
They bounded off her round-tower and her water-washed decks like pebbles.The Victim|Thomas Dixon
This castle is a strong square building, with a round-tower at each angle, and one of the same form at each side of the gateway.