1) Separate, it was used of land held by an individual, not in common ownership.
1491 vij acres of land and medowe ... lying severalle in iiij felds of Pudsey
1564 Rawdenfild ... for this xxx or xl yeres continually haith bene and yet is a severall inclosid ground
1566 all those landes ... liyinge severally in the Townefeldes of Thurstonland. It had legal implications, as in this use of the noun: 1535 towchyng his title whereby he clamys to have severaltie in certeyn closys, York. Examples where the meaning is ‘separate, distinct’ illustrate how the modern usage developed: 1529 the seruandes and tenantes of the seid Erle at twoo seuerall tymes toke certen wheate, Scorborough
1622 ‘Robert Wrangham for breaking the pinfold 3 several times’, Acomb. It was responsible for minor place-names as open-field enclosure took place: 1558-9 had the Agiestment of a Large parcel of Ground called the Severals which the Tennants ... fenced for him, Hatfield
1719 Great Severals, Beeston.