topmast

thumb|right|A traditional ship's mast, consisting of "lower" (i.e. Main-, Fore- or Mizzen-) mast, topmast and topgallant/royal mast. The topmast is highlighted in red. The masts of traditional sailing ships were not single spars, but were constructed of separate sections or masts, each with its own rigging. The topmast is one of these.

The topmast is semi-permanently attached to the upper front of the lower mast, at the top. Its shrouds run to the edges of the top, rather than to the sides of the hull, though long shrouds leading well aft to the hull, more in the manner of backstays, are sometimes seen. In accordance with the standard square rig sail plan, the topmast carries the topsail. In the late 19th century, however, topsails became so big that merchant ships began to divide them into two separate sails for easier handling; since these were still on the topmast they were known as upper and lower topsails to preserve the consistency of the naming scheme. The majority of large square-riggers today carry separate upper and lower topsails.