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

And at last she could make it out, for the black Roman numerals were just barely visible against their white ground, the brass hands glowed faintly.

From "Tuck Everlasting" by Natalie Babbit