1) The OED gives two meanings, one as a word for bracken, apparently not found in northern writers, and the other for a clump of bushes or briers.
Place-name writers take the second of these to be the source of minor names such as Brakes and Breaks. The meaning of the word in some Yorkshire references may not be clear but bracken was in common use so the likelihood is that ‘brake’ meant briers: 1503 the grounde where they grovyd [dug] is overgrovyn with bushes and brakes, Roundhay Park
1569 ‘they say that Edward Lockwodd scythed le brakes within the demesne’, Farnley Tyas
1616 Braykes from my common Christofer Idle 6 loads payd ijs, Brandsby
1679 Elizabeth Harrison found the pewther in a whin bush ... covered with breaks, Pannal.
2) As a noun this was a toothed instrument used in the preparation of flax and hemp. However, the same word was used for other craft instruments (OED) so the meaning is not always clear.
1582 ij breaks, a horse hecke, South Cave
1669 3 stone of hemp, one crab brake, Brayton
1747 a pair of brakes and other utensils for line dressing, Fishlake. The verb is on record from 1398 but again it had varied meanings: 1562 halfe my towe of hemp and flaxe that is brayked, Sutton Bonnington
1639 flacks and hempe unbraked, iiijs Selby. The meaning in the following case is obscure: 1546 I bequeath to William Watson, my prentice, the gere that he workithe with at Braycke and braycke with a blake jacket, Seacroft.