Wiktionary
n. A roll of fiber, used as a precursor to yarn.
Wikipedia
A rolag ( Scottish Gaelic: roileag) is a roll of fibre generally used to spin woollen yarn. A rolag is created by first carding the fibre, using handcards, and then by gently rolling the fibre off the cards. If properly prepared, a rolag will be uniform in width, distributing the fibres evenly. The word derives from the Scottish Gaelic word for a small roll. 1
Animal fibres have traditionally been used to create rolags, but today's spinners use many different fibre materials, including manufactured and plant fibres.
Usage examples of "rolag".
A bit at a time, she let new fibers from the rolag get caught in the twirling thread, until they were thread as well.
Bringing her new spindle and the rolags she had prepared that afternoon, Sandry took a chair beside Lark, who did her own spinning while helping the girl with hers.
She grubbed in her workbag, digging past rolags, scissors, skeins of finished yarn.
She had no rolags to prepare, not for the kind of spinning she had in mind.