abatis, abutment, advanced work, aegis, arc-boutant, arch dam, arm guard, backstop, balistraria, bamboo curtain, bank, banquette, bar, barbed-wire entanglement, barbican, barrage, barricade, barrier, bartizan, bastion, battlement, beam, bear-trap dam, beaver dam, boom, breakwater, breastwork, brick wall, buffer, bulkhead, bumper, buttress, buttress pier, buttressing, casemate, cheval-de-frise, circumvallation, citadel, cofferdam, contraceptive, contravallation, copyright, counterscarp, cover, crash helmet, curtain, cushion, dam, dashboard, defend, defense, demibastion, dike, ditch, dodger, drawbridge, earthwork, embankment, enclosure, entanglement, escarp, escarpment, face mask, fence, fend, fender, fieldwork, finger guard, flying buttress, foot guard, fort, fortalice, fortification, fortress, fuse, gate, glacis, goggles, governor, gravity dam, groin, guard, guardrail, hand guard, handrail, hanging buttress, hard hat, helmet, hydraulic-fill dam, insulation, interlock, iron curtain, jam, jetty, jutty, knee guard, knuckle guard, laminated glass, leaping weir, levee, life preserver, lifeline, lightning conductor, lightning rod, logjam, loophole, lunette, machicolation, mantelet, mask, merlon, milldam, moat, mole, mound, mudguard, nose guard, outwork, pad, padding, palisade, palladium, parados, parapet, patent, pier, pier buttress, pilot, portcullis, postern gate, preventive, prophylactic, protect, protective clothing, protective umbrella, rampart, ravelin, redan, redoubt, retaining wall, roadblock, rock-fill dam, safeguard, safety, safety glass, safety plug, safety rail, safety shoes, safety switch, safety valve, sally port, scarp, sconce, screen, seat belt, seawall, secure, shelter, shield, shin guard, shoulder, shutter dam, stockade, stone wall, stronghold, sun helmet, tenaille, umbrella, vallation, vallum, wall, weir, wicket dam, windscreen, windshield, work