(n.) The hindmost mast of a three-masted vessel, or of a yawl-rigged vessel.

advocate alpenstock antenna tower arm athletic supporter back backbone backing bandeau barbican bare pole bearer belfry bell tower boom bowsprit bra brace bracer bracket brassiere bumpkin buttress campanile cane carrier cervix club colossus column corset crook crossjack yard crosstree crutch cupola derrick dolphin striker dome fire tower flying jib boom fore jack fore-skysail mast fore-skysail yard fore-topgallant mast fore-topgallant yard fore-topmast foremast foreroyal mast foreroyal yard foreyard foundation garment fulcrum gaff girdle gooseneck guy guywire jack jib boom jock jockstrap king post lantern lazy jack lighthouse lower boom main-royal mast main-royal yard main-skysail mast main-topgallant mast mainmast mainstay maintainer martello martello tower masthead minaret mizzen mizzen-royal mast mizzenmast monument neck obelisk observation tower pagoda pilaster pillar pinnacle pole prop pylon pyramid reinforce reinforcement reinforcer rest resting place rigging shaft shoulder shroud skysail yard skyscraper spanker boom spanker gaff spar spars spine spire spreader sprit staff standing rigging standpipe stave stay steeple stick stiffener strengthener stupa support supporter sustainer tack bumpkin television mast timber tope topgallant mast topgallant yard topmast tour tower tree turret upholder walking stick water tower whisker boom whisker pole windmill tower yard yardarm