mainboom

mainboom

(ˈmeɪnˌbuːm)
n
(Nautical Terms) nautical the spar for the mainsail
References in classic literature ?
He cleared the danger of the mainsheet with a wild leap (although no less wild had been Van Horn's leap to rescue him), and found himself directly under the mainboom with the huge sail looming above him as if about to fall upon him and crush him.