S: (n) space (an empty area (usually bounded in some way between things)) "the architect left space in front of the building"; "they stopped at an open space in the jungle"; "the space between his teeth"
S: (n) cavern (any large dark enclosed space) "his eyes were dark caverns"
S: (n) matrix (an enclosure within which something originates or develops (from the Latin for womb))
S: (n) expanse (a wide and open space or area as of surface or land or sky)
S: (n) sheet (any broad thin expanse or surface) "a sheet of ice"
S: (n) stretch (a large and unbroken expanse or distance) "a stretch of highway"; "a stretch of clear water"
S: (n) slack, slack water (a stretch of water without current or movement) "suddenly they were in a slack and the water was motionless"
S: (n) opening, gap (an open or empty space in or between things) "there was a small opening between the trees"; "the explosion made a gap in the wall"
S: (n) pocket (an opening at the corner or on the side of a billiard table into which billiard balls are struck)
S: (n) foramen magnum (the large opening at the base of the cranium through which the spinal cord passes)
S: (n) breach (an opening (especially a gap in a dike or fortification))
S: (n) chasm (a deep opening in the earth's surface)
S: (n) abyss, abysm (a bottomless gulf or pit; any unfathomable (or apparently unfathomable) cavity or chasm or void extending below (often used figuratively))
S: (n) fault, faulting, geological fault, shift, fracture, break ((geology) a crack in the earth's crust resulting from the displacement of one side with respect to the other) "they built it right over a geological fault"; "he studied the faulting of the earth's crust"
S: (n) lenticel (one of many raised pores on the stems of woody plants that allow the interchange of gas between the atmosphere and the interior tissue)
S: (n) bolt-hole (a hole through which an animal may bolt when pursued into its burrow or den)
S: (n) mouth (an opening that resembles a mouth (as of a cave or a gorge)) "he rode into the mouth of the canyon"; "they built a fire at the mouth of the cave"
S: (n) rift (a gap between cloud masses) "the sun shone through a rift in the clouds"
S: (n) rip, rent, snag, split, tear (an opening made forcibly as by pulling apart) "there was a rip in his pants"; "she had snags in her stockings"
S: (n) window (an opening that resembles a window in appearance or function) "he could see them through a window in the trees"
S: (n) swath (the space created by the swing of a scythe or the cut of a mowing machine)
S: (n) angle (the space between two lines or planes that intersect; the inclination of one line to another; measured in degrees or radians)
S: (n) crotch, fork (the angle formed by the inner sides of the legs where they join the human trunk)
S: (n) axil (the upper angle between an axis and an offshoot such as a branch or leafstalk)
S: (n) helix angle (the constant angle at which a helix cuts the elements of a cylinder or cone)
S: (n) angular distance (the angular separation between two objects as perceived by an observer) "he recorded angular distances between the stars"
S: (n) latitude (the angular distance between an imaginary line around a heavenly body parallel to its equator and the equator itself)
S: (n) longitude (the angular distance between a point on any meridian and the prime meridian at Greenwich)
S: (n) declination, celestial latitude, dec ((astronomy) the angular distance of a celestial body north or to the south of the celestial equator; expressed in degrees; used with right ascension to specify positions on the celestial sphere)
S: (n) right ascension, RA, celestial longitude ((astronomy) the equatorial coordinate specifying the angle, measured eastward along the celestial equator, from the vernal equinox to the intersection of the hour circle that passes through an object in the sky; usually expressed in hours and minutes and seconds; used with declination to specify positions on the celestial sphere) "one hour of right ascension equals fifteen degrees"
S: (n) hour angle, HA ((astronomy) the angular distance of a celestial point measured westward along the celestial equator from the zenith crossing; the right ascension for an observer at a particular location and time of day)
S: (n) true anomaly (the angular distance of a point in an orbit past the point of periapsis measured in degrees)
S: (n) plane angle (an angle formed by two straight lines (in the same plane))
S: (n) spherical angle (an angle formed at the intersection of the arcs of two great circles)
S: (n) solid angle (an angle formed by three or more planes intersecting at a common point (the vertex))
S: (n) inclination, angle of inclination ((geometry) the angle formed by the x-axis and a given line (measured counterclockwise from the positive half of the x-axis))
S: (n) angle of attack (the acute angle between the direction of the undisturbed relative wind and the chord of an airfoil)
S: (n) critical angle (the smallest angle of incidence for which light is totally reflected)
S: (n) angle of reflection (the angle between a reflected ray and a line perpendicular to the reflecting surface at the point of incidence)
S: (n) angle of refraction (the angle between a refracted ray and a line perpendicular to the surface between the two media at the point of refraction)
S: (n) wave angle (the angle of arrival (or departure) of a radio wave with respect to the axis of an antenna array)
S: (n) void, vacancy, emptiness, vacuum (an empty area or space) "the huge desert voids"; "the emptiness of outer space"; "without their support he'll be ruling in a vacuum"
S: (n) pocket ((bowling) the space between the headpin and the pins behind it on the right or left) "the ball hit the pocket and gave him a perfect strike"