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lamb's wool

noun
  1. a soft, virgin wool possessing superior spinning qualities, shorn from a seven-month-old lamb.
  2. a fabric made from this wool.

Origin of lamb's wool

First recorded in 1545–55
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for lamb's wool

lamb's wool

noun
    1. fine soft wool obtained from a lamb at its first shearing
    2. (as modifier)lamb's-wool jumpers
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012