Definition of "mainyard"

The sails were split, the mainyard shivered, the wind blowing fresh, the night setting in; and all our chance was to make for Corfu--or, as F. pathetically called it, 'a watery grave.'

1880, John Nichol, Byron‎

A long line of red and white flags extends from the top of the mainyard to the helm and streamers flutter from the mastheads.

1914, E.H. Aitken, Concerning Animals and Other Matters‎