A species of estate in expectancy, created by operation of law, being the residue of an estate left in the grantor, to commence in possession after the determination of some particular estate granted out by him. 2 B1. Comm. 175; 2 Crabb, Real Prop. p. 978, s 2845. The residue of an estate left in the grantor or his heirs, or in the heirs of a testator, commencing in possession on the determination of a particular estate granted or devised. 1 Rev. St. N. Y. p. 718, (723,) s 12. An estate in reversion is where any estate is derived, by grant or otherwise, out of a larger one, leaving in the original owner an ulterior estate immediately expectant on that which is so derived; the latter interest being called the “particular estate,” as being only a small part or particula of the original one,) and the ulterior interest, the “reversion.” 1 Steph. Comm. 290. See REVERSION.