Completum

Completum is the neuter singular perfect passive participle of the Latin verb compleo, meaning to fill or to complete. In Latin, participles can function as adjectives or as nouns; completum commonly denotes “that which is completed” or “the completed thing” when used substantively.

It belongs to the participial paradigm completus (masculine), completa (feminine), completum (neuter). As a neuter adjective or noun, completum agrees with neuter nouns such as opus (a work) or factum (a deed). In use, it describes the result of completion rather than the act itself.

Typical phrases include opus completum (“a completed work”) and, less commonly, res completum in early legal or documentary Latin, though proper grammar would favor neuter nouns for agreement. In medieval glossaries, completum is sometimes treated as a substantive meaning “the completed matter.”

Today completum is mainly of interest to students of Latin grammar and historical linguistics. It is not used as an independent word in English; rather, it appears in Latin quotations and grammar references to illustrate participle agreement and nominalization.

See also: compleo, completus, completion.