Roman numerals

British  

plural noun

1. the letters used by the Romans for the representation of cardinal numbers, still used occasionally today. The integers are represented by the following letters: I (= 1), V (= 5), X (= 10), L (= 50), C (= 100), D (= 500), and M (= 1000). If a numeral is followed by another numeral of lower denomination, the two are added together; if it is preceded by one of lower denomination, the smaller numeral is subtracted from the greater. Thus VI = 6 (V + I), but IV = 4 (V – I). Other examples are XC (= 90), CL (= 150), XXV (= 25), XLIV (= 44). Multiples of a thousand are indicated by a superior bar: thus, ̅V = 5000, ̅X = 10 000, ̅X̅D = 490 000, etc

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Roman numerals Cultural  

1. Letters of the alphabet used in ancient Rome to represent numbers: I = 1; V = 5; X = 10; L = 50; C = 100; D = 500; M = 1000. The numbers one through ten are written I, II, III, IV, V, VI, VII, VIII, IX, and X. Roman numerals are often used to signify divisions of a long work, or of a work with many parts. They are also used to lend significance to something, as in Super Bowl VII. Formal designation of years may also be in Roman numerals: a.d. MCMLXXXIX = a.d. 1989.

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Example Sentences

I wished that the book’s sections, numbered I through X, had names in addition to their Roman numerals.

From The Wall Street Journal • Jan. 9, 2026

She said he began "wearing" his bed sheets, called his family to speak "in Roman numerals" and identified himself to fellow inmates as Jesus Christ.

From BBC • Jun. 27, 2025

A gift from the French, the sculpture holds a tablet inscribed with the date July 4, 1776 in Roman numerals, representing independence.

From Salon • Apr. 26, 2024

His suggestion: a red jacket with a patch on the breast pocket featuring the Lombardi Trophy and the Roman numerals of the Super Bowls that quarterback won.

From Los Angeles Times • Feb. 4, 2024

As they wound their way underground, Piper saw old graffiti gouged into the stones: Roman numerals, names and phrases in Italian.

From "The Mark of Athena" by Rick Riordan