praecludere

Praecludere is a Latin verb meaning to close off beforehand, to bar, to block access, or more broadly to prevent or preclude. The form derives from prae- “before” plus cludere “to close.” The English preclude comes from this Latin verb via late Latin and Old French.

In general use, praecludere can denote physical obstruction (shutting a passage or doors before someone arrives) as well as figurative prevention (to preclude a course of action, a claim, or a possibility). In legal and formal Latin, the sense of preventing or barring an entitlement or action is common, and the noun praeclusio or praeventio related to the concept of preclusion or preemptive blocking can be derived from the verb.

Grammatical note: praecludere belongs to the third conjugation. In the active voice, its present indicative forms are praecludo, praecludis, praecludit, praecludimus, praecluditis, praecludunt. The perfect active is formed with praeclusi, praeclusisti, praeclusit, and the supine is praeclusum. The passive uses the endings praecludor, praecluderis, praecluditur, praecludimur, praecludimini, praecluentur. The participle praeclusus (and feminine/neuter forms) means “precluded” and is used in compound expressions.

Examples: Hostes vias praecludunt. (The enemies block off the roads.) In legal Latin, acta quae praecludunt rem in posterum saepe referuntur as praecisiones of preclusion.

See also: claudo, clausus, prae- prefixes, praecedere (to go before), praeclusio.