Abyss, Adit, Approach, Aqueduct, Bore, Bottom, Bottoms, Breach, Break, Bunker, Burrow, Canal, Canyon, Carve, Cave, Cavity, Chamfer, Channel, Chap, Chasm, Check, Chimney, Chink, Chisel, Cleave, Cleft, Col, Concealment, Conduct, Conduit, Convey, Couloir, Course, Cover, Covert, Crack, Cranny, Crash, Crevasse, Crevice, Crimp, Cut, Dado, Quarry, Ravine, Rent, Rifle, Rift, Rime, Rupture, Rut, Sap, Scoop, Score, Scrabble, Scrape, Scratch, Seam, Shelter, Shovel, Sink, Siphon, Slit, Slot, Spade, Split, Streak, Trespass, Trough, Tunnel, Vale, Valley, Verge, Void, Wadi, Way, Wrinkle, Dale, Defile, Dell, Delve, Dig, Dingle, Ditch, Donga, Drain, Draw, Dredge, Drill, Drive, Duct, Dugout, Earth, Egress, Encroach, Engrave, Entrance, Entrench, Entrenchment, Excavate, Excavation, Exit, Fault, Fissure, Flaw, Flute, Foxhole, Fracture, Funnel, Furrow, Gallery, Gap, Gape, Gash, Gill, Glen, Gorge, Gouge, Groove, Ground, Grove, Grub, Gulf, Gully, Gutter, Hole, Impinge, Impose, Incision, Infiltrate, Infringe, Ingress, Insinuate, Interfere, Interpose, Intervene, Intrude, Invade, Joint, Kennel, Kloof, Leak, Lower, Mine, Moat, Notch, Obtrude, Open, Opening, Parallel, Pass, Passage, Passageway, Pipe, Pleat