Which type of estate is characterized by ownership with an indeterminate length?

The type of estate characterized by ownership with an indeterminate length is a freehold estate. Freehold estates are ownership interests in real property that are not limited by time and can last indefinitely. This means that the owner has the right to use, lease, or sell the property without a predetermined end date.

In contrast, leasehold estates have a specific duration, such as a year or month, after which the right to occupy the property reverts to the landlord. Tenancy at sufferance occurs when a tenant remains in possession of property after their lease has expired, but this condition is typically temporary and can be terminated by the landlord. Joint tenancy involves co-ownership of property by two or more individuals with rights of survivorship, but it does not imply indeterminate length in the same sense as a freehold estate. Therefore, a freehold estate best embodies the concept of ownership without a fixed or limited duration.