Forfang
Black's Law Dictionary · Henry Campbell Black, M.A. · 1910
Black's Law Dictionary
In old English law
The taking of provisions from any per sen in fairs or markets before the royal purveyors were served with necessaries for the sovereign.
Cowell.
Also the seizing and rescuing of stolen or strayed cattle from the hands of a thief or of those having illegal possession of them; also the reward fixed for such rescue.