THESAURUS
arrowlike, billiard table, bowling green, dead flat, dead level, dead straight, direct, earth, esplanade, even, flat, flatland, flattened, floor, flush, ground, homaloid, homaloidal,
horizontal axis,
horizontal fault,
horizontal line,
horizontal parallax,
horizontal plane,
horizontal projection, in a line, ledge, level, level line, level plane, lineal, linear, mean sea level, parterre, plain, plane, platform, prairie, prone, rectilineal, rectilinear, right, rolled, ruler-straight, sea level, sea of grass, smooth, smoothed out, smoothened, squashed, squashed flat, steppe, straight, straight-cut, straight-front, straight-side, streamlined, supine, table, tabloid, tabular, terrace, trodden, trodden flat, true, unbending, unbent, unbowed, unbroken, uncurved, undeflected, undeviating, undistorted, uninterrupted, unswerving, unturned, upright, vertical, water level
ROGET THESAURUS
Horizontality
N
horizontality, flatness, level, plane, stratum, dead level, dead flat, level plane, recumbency, lying down, reclination, decumbence, decumbency, discumbency, proneness, accubation, supination, resupination, prostration, azimuth, plain, floor, platform, bowling green, cricket ground, croquet ground, croquet lawn, billiard table, terrace, estrade, esplanade, parterre, table land, plateau, ledge, butte, mesa (plain), level, spirit level,
horizontal, level, even, plane, flat, flat as a billiard table, flat as a bowling green, alluvial, calm, calm as a mill pond, smooth, smooth as glass, recumbent, decumbent, procumbent, accumbent, lying, prone, supine, couchant, jacent, prostrate, recubant, horizontally, on one's back, on all fours, on its beam ends.