What does "ouster" mean?

Ouster: A putting out of possession; dispossession; ejection; disseizin. Ouster of the freehold is effected by abatement, intrusion, disseizin, discontinuance, or deforcement. Blackstone. Ouster le main. Etym: [Ouster + F. la main the hand, L. manus.] (Law) A delivery of lands out of the hands of a guardian, or out of the king's hands, or a judgement given for that purpose. Blackstone.