The Collaborative International Dictionary
Corrugate \Cor"ru*gate\ (-g?t), v. t. [imp. & p. p. Corrugated (-g?`t?d); p. pr. & vb. n. Corrugating (-g?`t?ng).] To form or shape into wrinkles or folds, or alternate ridges and grooves, as by drawing, contraction, pressure, bending, or otherwise; to wrinkle; to purse up; as, to corrugate plates of iron; to corrugate the forehead.
Corrugated iron, sheet iron bent into a series of alternate ridges and grooves in parallel lines, giving it greater stiffness.
Corrugated paper, a thick, coarse paper corrugated in order to give it elasticity. It is used as a wrapping material for fragile articles, as bottles.
Wiktionary
vb. (present participle of corrugate English)
Usage examples of "corrugating".
In hot weather the sun would draw thermal gradients from the roadside stream, corrugating the house like an image on a rippling banner.
Then she cocked her arms akimbo and smiled, wrinkles corrugating every inch of her motherly face.
The door cracked Broonzer on the forehead, actually corrugating the bill on his Heston hat.