N. 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, 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, piercing, terebration, empalement, pertusion|, puncture, acupuncture, penetration, key, opener, master key, password, combination, passe-partout

V. open, ope, gape, yawn, bilge, fly open, perforate, pierce, empierce|, tap, bore, drill, mine, tunnel, transpierce, transfix, enfilade, impale, spike, spear, gore, spit, stab, pink, puncture, 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, pop open, blow open, pry open, tear open, pull open

Adj. 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

Int. open sesame

N. passage, transmission, permeation, penetration, interpenetration, transudation, infiltration, endosmose exosmose, endosmosis, intercurrence, ingress, egress, path, conduit, opening, journey, voyage

V. pass, pass through, perforate, penetrate, permeate, thread, thrid, enfilade, go through, go across, go over, pass over, cut across, ford, cross, pass and repass, work, make one's way, thread one's way, worm one's way, force one's way, make a passage form a passage, cut one's way through, find its way, find its vent, transmit, make way, clear the course, traverse, go over the ground

Adj. passing, intercurrent, endosmosmic, endosmotic

Adv. en passant