Architecture Terms – K A B C D E F G H I J K L M N O P Q R S T U V W X Y Z Photo by Laura Chouette, via Unsplash Key patternA repeating design consisting of interwoven vertical and horizontal lines, including the Greek key pattern in T, L, or G with squared corners. Cadop, CC0 , via Wikimedia Commons KeystoneThe center stone in an arch. Photo by Nat Belfort, via Unsplash King PostThe vertical post connecting the triangular truss with the base.