Ditch dug as a fortification and usually filled with water.

synonym: moat.

Roget 717: defense, protection, guard, ward; shielding etc. v.; propugnation^†, preservation etc. 670; guardianship.    area defense; site defense.    self-defense, self-preservation; resistance etc. 719.    safeguard etc. (safety) 664; balistraria^†; bunker, screen etc. (shelter) 666; camouflage etc. (concealment) 530; fortification; munition, muniment^†; trench, foxhole; bulwark, fosse^†, moat, ditch, entrenchment, intrenchment^†; kila^†; dike, dyke; parapet, sunk fence, embankment, mound, mole, bank, sandbag, revetment; earth work, field-work; fence, wall dead wall, contravallation^†; paling etc. (inclosure) 232; palisade, haha, stockade, stoccado^†, laager^†, sangar^†; barrier, barricade; boom; portcullis, chevaux de frise [Fr.]; abatis, abattis^†, abbatis^†; vallum^†, circumvallation^†, battlement, rampart, scarp; escarp^†, counter-scarp; glacis, casemate^†; vallation^†, vanfos^†.    buttress, abutment; shore etc. (support) 215.    breastwork, banquette, curtain, mantlet^†, bastion, redan^†, ravelin^†; vauntmure^†; advance work, horn work, outwork; barbacan^†, barbican; redoubt; fort-elage [Fr.], fort-alice; lines.    loophole, machicolation^†; sally port.    hold, stronghold, fastness; asylum etc. (refuge) 666; keep, donjon, dungeon, fortress, citadel, capitol, castle; tower of strength, tower of strength; fort, barracoon^†, pah^†, sconce, martello tower^†, peelhouse^†, blockhouse, rath^†; wooden walls.    [body armor] bulletproof vest, armored vest, buffer, corner stone, fender, apron, mask, gauntlet, thimble, carapace, armor, shield, buckler, aegis, breastplate, backplate^†, cowcatcher, face guard, scutum^†, cuirass, habergeon^†, mail, coat of mail, brigandine^†, hauberk, lorication^†, helmet, helm, bassinet, salade^†, heaume^†, morion^†, murrion^†, armet^†, cabaset^†, vizor^†, casquetel^†, siege cap, headpiece, casque, pickelhaube, vambrace^†, shako etc. (dress) 225.    bearskin; panoply; truncheon etc. (weapon) 727.    garrison, picket, piquet; defender, protector; guardian etc. (safety) 664; bodyguard, champion; knight-errant, Paladin; propugner^†.    bulletproof window.    hardened site.    ... show more

Roget 232: inclosure, envelope; case etc. (receptacle) 191; wrapper; girdle etc. 230.    pen, fold; pen fold, in fold, sheep fold; paddock, pound; corral; yard; net, seine net.    wall, hedge, hedge row; espalier; fence etc. (defense) 717; pale, paling, balustrade, rail, railing, quickset hedge, park paling, circumvallation^†, enceinte, ring fence.    barrier, barricade; gate, gateway; bent, dingle [U.S.]; door, hatch, cordon; prison etc. 752.    dike, dyke, ditch, fosse^†, moat.    ... show more

Roget 259: furrow, groove, rut, sulcus [Anat.], scratch, streak, striae, crack, score, incision, slit; chamfer, fluting; corduroy road, cradle hole.    channel, gutter, trench, ditch, dike, dyke; moat, fosse^†, trough, kennel; ravine etc. (interval) 198; tajo [U.S.], thank-ye-ma'am [U.S.].    ... show more

Dutch: gracht, ringgracht, slotgracht, vest, vestinggracht
Polish: fosa