precarius

Precarius is a Latin adjective meaning precarious, dependent, or obtained by begging. In Roman law, the term also designates a person who holds something by a precarium—a revocable grant of permission to use another’s property. The grantor allows use for an indefinite period, but may recall the permission at any time; ownership remains with the grantor, and the user is typically obliged to return the thing when recalled.

The contract of precarium is distinguished by its revocability and its focus on use rather than transfer of ownership. The user generally obtains the right to use the property (usum) but not to fruits (fructus) or improvements, though the precise rights could vary by period and jurist. Compared with other Roman arrangements, such as mutuum (loan of fungible goods with transfer of ownership) and commodatum (use with a duty to return, not necessarily revocable), precarium embodies a more fragile, conditional form of permission.

Historically, precarium was used to regulate temporary grants of land or goods while preserving the owner’s control. It gave rise to disputes over the scope of revocation, the duration of continued use after recall, and the allocation of any fruits or outputs produced during the grant. In legal theory, precarium is cited as an example of a revocable license and the limits of permission-based possession within Roman property law.

In modern usage, precarius survives mainly as a scholarly term in the study of Roman law and as an adjective in some languages to denote something precarious or dependent. The noun form precarium and the concept itself are mainly of historical and philological interest today.