decem

Decem is the Latin word for ten and functions as a cardinal numeral in classical Latin, used to modify nouns and in various compound forms. In everyday Latin, decem appears in phrases such as decem annos, meaning ten years, and more broadly in expressions denoting ten units of something.

Etymology and relatives: Decem derives from the Proto-Italic root *dek̂ʷm-, itself from the Proto-Indo-European root *déḱm̥s, connected to the Greek deka- and to the English prefix deca- through later linguistic development. In Latin, decem provided the base for several words and titles that emphasize the number ten.

Notable uses in Roman history: Decemviri refers to boards of ten magistrates appointed at different times in the Roman Republic. The most famous were the First Decemvirate (451–450 BCE), which produced the Law of the Twelve Tables, and the Second Decemvirate (449 BCE), which briefly consolidated power and was associated with political crisis and the restoration of the traditional magistracies. These institutions illustrate how the term decem shaped political organization and legal development in early Rome.

Modern usage and derivatives: The concept of ten years is expressed in English terms such as decennial and decennium, both derived from Latin decennium (ten-year period). While decem remains primarily a historical and philological term, its influence persists in modern vocabulary through these derivatives and in the continued use of decemvir and decemvirate in historical writings.