The Collaborative International Dictionary
Gaff-topsail
Gaff-topsail \Gaff`-top"sail\, n. (Naut.) A small triangular sail having its foot extended upon the gaff and its luff upon the topmast.
Wiktionary
gaff-topsail
n. (context nautical English) A small triangular sail having its foot extended upon the gaff and its luff upon the topmast.