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This term is used as both a noun and a verb. When an Estate in land is granted that is less than the entire interest (that is, not Fee simple Freehold), then it is expected that the whole interest will 'revert' to the original grantor at some point. For example, when a Leasehold Tenancy expires, there is typically a reversion to the freehold owner. During the period of the lease, the freeholder is thus said to 'own the reversion'. A reversion is a form of title and may be income-generating. It can therefore be assigned (i.e., sold) as such.