decimal

American  

[des-uh-muhl, des-muhl] / ˈdɛs ə məl, ˈdɛs məl /

adjective

1. pertaining to tenths or to the number 10.

2. proceeding by tens.

   a decimal system.

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noun

1. decimal fraction.

decimal British  

/ ˈdɛsɪməl /

noun

1. Also called: decimal fraction.  a fraction that has a denominator of a power of ten, the power depending on or deciding the decimal place. It is indicated by a decimal point to the left of the numerator, the denominator being omitted. Zeros are inserted between the point and the numerator, if necessary, to obtain the correct decimal place

2. any number used in the decimal system

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adjective

1. 1. relating to or using powers of ten

   2. of the base ten

2. (prenominal) expressed as a decimal

decimal Scientific  

/ dĕs′ə-məl /

1. A representation of a real number using the base ten and decimal notation, such as 201.4, 3.89, or 0.0006.

2. A decimal fraction.

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Other Word Forms

• decimally
  adverb

Etymology

Origin of decimal

First recorded in 1600–10; from Medieval Latin decimālis “of tenths,” equivalent to Latin decim(a) “tenth” (derivative of decem “ten” ) + -ālis adjective suffix; see ten, -al ¹

Explanation

A decimal is a fraction written in a special form. Instead of writing 1/2, for example, you can express the fraction as the decimal 0.5, where the zero is in the ones place and the five is in the tenths place. Decimal comes from the Latin word decimus, meaning tenth, from the root word decem, or 10. The decimal system, therefore, has 10 as its base and is sometimes called a base-10 system. Decimal can also specifically refer to a number in the decimal system. As an adjective, decimal means something related to this numbering system. The decimal point, for example, refers to the period that separates the ones place from the tenths place in decimal numbers.

Example Sentences

If Judy says she can’t make it as a clerk, she’ll stay up all night learning the Dewey Decimal System.

From Salon • Jun. 9, 2025

She criticized the Dewey Decimal System for including “overwhelmingly Christian” works in a 2013 article called “Queering the Catalog: Queer Theory and the Politics of Correction.”

From Washington Times • Aug. 30, 2023

I memorized the Dewey Decimal number so there was no evidence of what I was after.

From Seattle Times • Jun. 2, 2023

Volumes were organized by topic but “certainly … not using the Dewey Decimal system,” Nick Malgieri, a noted pastry chef and author who frequented Mrs. Longone’s store, admiringly recalled.

From Washington Post • Aug. 10, 2022

Visitors also encountered the latest and arguably most important organizational invention of the century, the vertical file, created by Melvil Dewey, inventor of the Dewey Decimal System.

From "The Devil in the White City" by Erik Larson

Related Words

• figure
• statistic
• sum
• total