To form or shape into wrinkles or folds or into alternating ridges and grooves. (Merriam – Webster)
To draw or bend into folds or alternate furrows and ridges. (Dictionary.com)
To wrinkle, as the skin or face. (Dictionary.com)
Contract or cause to contract into wrinkles or folds. (Oxford Dictionaries)
To fold or be folded into alternate furrows and ridges. (Collins Dictionary)
Folded into furrows and ridges; wrinkled. (Collins Dictionary)
Corrugate paper filter.