Synonyms and related words :
arrowlike, dead straight, direct, even, flat, horizontal, in a line, level, lineal, linear, rectilineal, right, ruler-straight, smooth, straight, straight-cut, straight-front, straight-side, streamlined, TRUE, unbending, unbent, unbowed, unbroken, uncurved, undeflected, undeviating, undistorted, uninterrupted, unswerving, unturned, upright, vertical