Word Study
squinch
CIDE DICTIONARY
squinch, n. [Corrupted fr. sconce.].
A small arch thrown across the corner of a square room to support a superimposed mass, as where an octagonal spire or drum rests upon a square tower; -- called also sconce , and sconcheon . [1913 Webster]
OXFORD DICTIONARY
squinch, n. a straight or arched structure across an interior angle of a square tower to carry a superstructure, e.g. a dome.
Etymology
var. of obs. scunch, abbr. of SCUNCHEON
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