topmast(n = noun.artifact) - the mast next above a lower mast and topmost in a fore-and-aft rig;
is a kind of mast
has particulars: fore-topmast, main-topmast, royal mast, topgallant, topgallant mast
The second mast, or that which is next above the lower mast, and below the topgallant mast. [1913 Webster]
topmast, n. Naut. the mast next above the lower mast.