Open English Wordnet
Nouns
(n)perpendicular, perpendicular style, English-Gothic, English-Gothic architecturea Gothic style in 14th and 15th century England; characterized by vertical lines and a four-centered (Tudor) arch and fan vaulting
(n)plumb line, perpendiculara 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
Adjectives
(a)vertical, perpendicularat right angles to the plane of the horizon or a base line“a vertical camera angle”, “the monument consists of two vertical pillars supporting a horizontal slab”, “measure the perpendicular height”