1) A kind of kersey or coarse woollen cloth.
A term first noted in the Act of 1523. Examples are met with soon afterwards in Yorkshire: 1539-40 one orige tawnaye dosyn of my best making, Leeds
1560 I will ther be brought too dosans of clothe and them to be delte to poor people imediatlye after my deth, Leeds.
2) Literally twelve.
1463 15 dos’ felthattes, Hull but used as a locally defined measure by charcoal-burners, colliers, ironstone miners and clothiers, certainly from as early as the fourteenth century: 1348 ‘2s for a dozen ironstones’, Wakefield. Sir John Langton’s nine-year lease to his son confirms its use: 1454 Sir John hath latyn to ferme [let to farm] all his mynes of Iryn Ure … yheldyng therefore le dosan tale for evere dosan, Farnley near Leeds. ‘Tale’ was used when quantity was being estimated by the number counted as opposed to an actual weight, with reference to whatever implement held the ironstone: that may have been by the corf if the quantity was measured at the mine entrance or by the horse-load as it was conveyed away. At Sir Richard Sherburn’s Esholt ironworks the charcoal-burners’ dozen is explained: 1567-8 everye dousson is 12 quarter of colle and the quarter ys a horsselode . Coal-mining examples are much later and the measurement less certain: 1729-31 each man two dozen of coles a day, Swillington
1760 Given to three of the Miners for getting 40 Doz. 1s 6d, Tong. For clothiers, wool was also measured in dozens: 1506 vj dosan garne of wolds or Lyncolnshire woll, York
1617 two dozans of woole with stuffe to litte them withall, Bingley.