13 letters · 20 points in Scrabble
noun a straight line at right angles to another line
noun a Gothic style in 14th and 15th century England; characterized by vertical lines and a four-centered (Tudor) arch and fan vaulting
noun 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
originDerived from Middle French perpendiculaire, from Old French perpendiculer, from Latin perpendiculum (“plumb line”).
Etymology from Wiktionary, CC BY-SA 3.0