pleated

Concise Oxford English Dictionary © 2008 Oxford University Press:
pleat/pliːt/

▶noun

• 1 a double or multiple fold in a garment or other item made of cloth, held by stitching the top or side.

• 2 a plait.

▶verb (often as adj. pleated) fold or form into pleats.

– origin ME: var. of plait.