Webster's Revised Unabridged Dictionary · 1913

Rumple

Rumple , verb, transitive and intransitive

[Compare rimple, and Dutch rimpelen to wrinkle, rompelig rough, uneven, German rumpfen to wrinkle, Middle High German rumphen, Old High German rimpfan, Greek "ra`mfos the crooked beak of birds of prey, {not transcribed} to roam.]

To make uneven; to form into irregular inequalities; to wrinkle; to crumple; as, to rumple an apron or a cravat.
They would not give a dog's ear of their most rumpled and ragged Scotch paper for twenty of your fairest assignats. — Burke

Rumple , noun

A fold or plait; a wrinkle. — Dryden