Glen plaid

noun

a plaid pattern of muted colors or of black or gray and white, especially one in which two dark and two light stripes alternate with four dark and four light stripes, both vertically and horizontally, forming a crossing pattern of irregular checks.
a fabric having such a pattern.
a garment made of such a fabric.

Origin of Glen plaid

1925–30; orig. Glenurquhart (or Glen Urquhart) plaid (check, tweed, etc.), after a valley of that name in Invernesshire, Scotland

Also called Glen check.