A temporary mast to replace one that has broken off.

Roget 147: substitution, commutation; supplanting etc. v.; metaphor, metonymy etc. (figure of speech) 521.    [Thing substituted] substitute, ersatz, makeshift, temporary expedient, replacement, succedaneum; shift, pis aller [Fr.], stopgap, jury rigging, jury mast, locum tenens, warming pan, dummy, scapegoat; double; changeling; quid pro quo, alternative.    representative etc. (deputy) 759; palimpsest.    price, purchase money, consideration, equivalent.    ... show more

Roget 666: refuge, sanctuary, retreat, fastness; acropolis; keep, last resort; ward; prison etc. 752; asylum, ark, home, refuge for the destitute; almshouse^†; hiding place etc. (ambush) 530; sanctum sanctorum [Lat.] etc. (privacy) 893.    roadstead, anchorage; breakwater, mole, port, haven; harbor, harbor of refuge; seaport; pier, jetty, embankment, quay.    covert, cover, shelter, screen, lee wall, wing, shield, umbrella; barrier; dashboard, dasher [U.S.].    wall etc. (inclosure) 232; fort etc. (defense) 717.    anchor, kedge; grapnel, grappling iron; sheet anchor, killick^†; mainstay; support etc. 215; cheek etc. 706; ballast.    jury mast; vent-peg; safety valve, blow-off valve; safety lamp; lightning rod, lightning conductor; safety belt, airbag, seat belt; antilock brakes, antiskid tires, snow tires.    means of escape etc. (escape) 671; lifeboat, lifejacket, life buoy, swimming belt, cork jacket; parachute, plank, steppingstone; emergency landing.    safeguard etc. (protection) 664.    ... show more