Small accumulations of fibres on the surface of a fabric. Pills can develop during wear, and are held to the fabric by an entanglement with the surface fibres of the material
Textile Resource (http://www.textile.org.uk)
The tendency of some yarns to form little balls of short, tangled fibers on the surface. This tendency can be reduced (or removed) by removing the short fibers (combing) or by adding additional twist.
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