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The English name of several plants of the genus Dipsacus, nat. order Dipsaceae. The fuller's thistle (D. Fullonum) is allied to the teasel (D. sylvestris) which grows wild in hedges. It is cultivated, in those districts of England where cloth is manufactured, for the sake of the awns of the head, which are employed to raise the nap of woollen cloths. For this purpose the heads are fixed round the circumference of a large broad wheel or drum so as to form a kind of brush. The wheel is made to turn round while the cloth is held against the brush thus formed, and the fine hooked awn of the teasel readily insinuates itself into the web, and draws out with it some of the fine fibres of the wool. These are afterwards shorn smooth, and leave the cloth with the fine velvet-like nap which is its peculiar appearance: the burr of the plant: any contrivance used as a substitute for teasels in the dressing of woollen cloth. Written also TEAZLE.

To subject to the action of teasels in the dressing of woollen cloth: to raise a nap on by the action of the teasel. Written also TEAZLE.