hole, foramen; puncture, perforation; fontanel; transforation; pinhole, keyhole, loophole, porthole, peephole, mousehole, pigeonhole; eye of a needle; eyelet; slot., opening; aperture, apertness; hiation, yawning, oscitancy, dehiscence, patefaction, pandiculation; chasm (interval)., embrasure, window, casement; abatjour; light; sky light, fan light; lattice; bay window, bow window; oriel; dormer, lantern., outlet, inlet; vent, vomitory; embouchure; orifice, mouth, sucker, muzzle, throat, gullet, weasand, wizen, nozzle; placket., portal, porch, gate, ostiary, postern, wicket, trapdoor, hatch, door; arcade; cellarway, driveway, gateway, doorway, hatchway, gangway; lich gate., way, path; thoroughfare; channel; passage, passageway; tube, pipe; water pipe; air pipe; vessel, tubule, canal, gut, fistula; adjutage, ajutage; ostium; smokestack; chimney, flue, tap, funnel, gully, tunnel, main; mine, pit, adit, shaft; gallery., alley, aisle, glade, vista., bore, caliber; pore; blind orifice; fulgurite, thundertube., porousness, porosity; sieve, cullender, colander; cribble, riddle, screen; honeycomb., apertion, perforation; pierching; terebration, empalement, pertusion, puncture, acupuncture, penetration., opener, key, master key, passe-partout.

open, ope, gape, yawn, bilge; fly open., perforate, pierce, empierce, tap, bore, drill; mine (scoop out); tunnel; transpierce, transfix; enfilade, impale, spike, spear, gore, spit, stab, pink, puncture, punch, lance, stick, prick, riddle, punch; stave in., cut a passage through; make way for, make room for., uncover, unclose, unrip; lay open, cut open, rip open, throw open.

open; perforated; perforate; wide open, ajar, unclosed, unstopped; oscitant, gaping, yawning; patent., tubular, cannular, fistulous; pervious, permeable; foraminous; vesicular, vasicular; porous, follicular, cribriform, honeycombed, infundibular, riddled; tubulous, tubulated; piped, tubate., opening; aperient.