Xii

XII is the Roman numeral for the number twelve. It is formed by X, representing ten, followed by II, representing two. In Roman numerals, XII is written additively rather than using subtractive notation.

The term XII derives from the Latin word duodecim, meaning twelve, itself formed from duo (two) and decem (ten). The numeral system using XII has been used since antiquity for numbering years, chapters, volumes, and other ordered items, and it remains common in clock faces and formal inscriptions.

In historical and cultural contexts, XII is frequently employed to denote a group of twelve, such as the Twelve Apostles or the Twelve Tribes of Israel. The Twelve Tables (Leges XII tabularum) are a foundational early Roman legal code. Beyond religious and legal uses, XII commonly appears as a label for the twelfth item in a sequence, a chapter number, or a year designation in some traditions.

In mathematics, twelve is a composite number with divisors 1, 2, 3, 4, 6, and 12. It is the smallest number with six divisors and is considered highly composite. Twelve also underpins the duodecimal (base-12) numbering system used in some cultural and historical contexts. In daily life, the concept of a dozen—twelve units—occurs frequently in commerce and timekeeping, where a twelve-hour cycle is common.

Overall, XII functions as a compact symbol for twelve, with lasting utility across mathematics, history, religion, and everyday counting.