a soft, slightly napped fabric of wool or wool and another fiber, used for trousers, jackets, shirts, etc.

a soft, warm, light fabric of cotton or cotton and another fiber, thickly napped on one side and used for sleepwear, undergarments, sheets, etc.

flannels,

an outer garment, esp. trousers, made of flannel.

woolen undergarments.

British .

a washcloth.

Informal . nonsense; humbug; empty talk.

Informal . flattery; insincere or overdone praise.

to cover or clothe with flannel.

to rub with flannel.