squinch

Etymology 1

Alteration of earlier scunch (“back part of the side of an opening”), short for scuncheon.

noun

1. (architecture) A structure constructed between two adjacent walls to aid in the transition from a polygonal to a circular structure, as when a dome is constructed on top of a square room.

Etymology 2

Uncertain. Probably blend of squint + pinch. Compare squink-eyed, variant of squint-eyed, so perhaps it is at least partly an altered form of squint.

verb

1. (transitive) To scrunch up (one's face, etc.).
   The president squinched his face and bit his lip and seemed too antsy to stand still. March 15, 2008, Gail Collins, “George Speaks, Badly”, in New York Times