also squirrelly, 1876, “reminiscent in some way of a squirrel,” from squirrel (n.) + -ly (1). Earlier was squirrelish (1834). From 1895 as “abounding in squirrels.” Related: Squirreliness.
squinch
squint
squire
squirm
squirrel
squirrely
squirt
squish
squishy
squiz
*sreu-