1) As a noun, this referred to a shared area of common grazing; as a verb it was the right to share in a common.
1560 alle and singler medous, pastures, fedynges, commons, comons of pastures, right of common, entercomons, great woddes and underwoddes, Pickering
1600 Intercommoners in the Lordship of Setrington ... Md that the Inhabitants of Norton & Sutton haue libertie of Intercomon without Norton Dike vnto the Crosse of the moore boath winter & somer with all maner of cattle. In a dispute in 1627 about common rights, the territory of the villages of Meltham, Marsden and Lingards was said to ascend to [the] height of the mores which ly above the villages all of which would have intercommon and turbary above their townes.