topgallant vs topgallant sail

topgallant and topgallant sail both are nouns.

Word	Noun	Adjective	Verb	Adverb
topgallant	Yes	No	No	No
topgallant sail	Yes	No	No	No

As nouns, topgallant and topgallant sail are synonyms defined as:

topgallant and topgallant sail: a sail set on a yard of a topgallant mast

topgallant (noun)	topgallant sail (noun)
a mast fixed to the head of a topmast on a square-rigged vessel	a sail set on a yard of a topgallant mast
a sail set on a yard of a topgallant mast