godan verb (-mu), intransitive verb
get wrinkled; become wrinkled
Intransitive verb describing something becoming wrinkled or creased, often used for skin, fabric, or paper. The suffix ばむ adds a sense of 'showing signs of' or 'becoming'.
年を取ると、肌が皺ばんでくる。
As you get older, your skin becomes wrinkled.
このシャツは洗うとすぐ皺ばむ。
This shirt gets wrinkled easily after washing.
Compound of 皺 (shiwa, 'wrinkle') + suffix ばむ (-bamu, 'to show signs of, to become'). The suffix ばむ attaches to nouns to form verbs indicating a tendency or appearance.