SLUB is validvalid

material with irregular appearance [adj SLUBBER, SLUBBEST] / to draw out and twist slightly [v SLUBBED, SLUBBING, SLUBS]

4,577 of 196,601 in NWL2023·also valid in CSW24

pertaining to a soft thick yarn, also SLUBB [adj SLUBBER, SLUBBEST] / to twist fibre after carding to prepare it for spinning [v SLUBBED, SLUBBING, SLUBS]