Synonyms to loophole

abatis, advanced work, balistraria, bank, banquette, barbed-wire entanglement, barbican, barricade, barrier, bartizan, bastion, battlement, breastwork, bulwark, casemate, cheval-de-frise, circumvallation, contravallation, counterscarp, curtain, demibastion, dike, drawbridge, earthwork, enclosure, entanglement, escarp, escarpment, fence, fieldwork, fortalice, fortification, glacis, lunette, machicolation, mantelet, merlon, mound, outwork, palisade, parados, parapet, portcullis, postern gate, rampart, ravelin, redan, redoubt, sally port, scarp, sconce, stockade, tenaille, vallation, vallum, work, air hole, CAT, aerospace, aerosphere, air duct, air passage, air pocket, air shaft, air tube, airspace, airway, armhole, blowhole, breathing hole, bullet-hole, bump, bunghole, ceiling, cringle, crosswind, deadeye, empty space, eye, eyelet, favorable wind, fog, front, gasket, grommet, guide, head wind, high-pressure area, hole, ionosphere, jetstream, keyhole, knothole, loop, louver, louverwork, low-pressure area, manhole, mousehole, naris, nostril, overcast, peephole, pigeonhole, pinhole, placket, placket