Ключевые слова: aperture, breach, break, burrow, cave, cavern, cavity, chamber, chasm, chink, cistern, cleft, covert, crack, cranny, crater, cut, den, dent, depression, dimple, dip, excavation, eyelet, fissure, foramen, fracture, gap, gash, gorge, hollow, hovel, keyhole, lacuna, lair, leak, mouth, nest, niche, nick, notch, orifice, outlet, passage, peephole, perforation, pit, pocket, pockmark, puncture, rent, retreat, scoop, shaft, shelter, space, split, tear, tunnel, vacuity, vent, void, window,