Synonyms for Perpendicular (same or very similar meaning)
WordNet sense 1 (a Gothic style in 14th and 15th century England; characterized by vertical lines and a four-centered (Tudor) arch and fan vaulting):
English-Gothic, English-Gothic architecture, perpendicular style
WordNet sense 2 (a cord from which a metal weight is suspended pointing directly to the earth's center of gravity; used to determine the vertical from a given point):
plumb line
WordNet sense 3 (having a set of mutually perpendicular axes; meeting at right angles):
orthogonal
WordNet sense 4 (forming a right angle):
normal
WordNet sense 5 (in a vertical position; not sloping):
upright
WordNet sense 6 (at right angles to the plane of the horizon or a base line):
vertical
WordNet sense 7 (having a sharp inclination):
steep
From the ODE community, based on WordNet
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