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Synonyms

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.


noun

  • decimals
    plural
  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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

adjective

    1. relating to or using powers of ten

    2. of the base ten

  1. (prenominal) expressed as a decimal

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
decimal Scientific  
/ dĕsə-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.


Other Word Forms

Derived Forms

Inflected Forms

Nouns

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.

Keep Reading on Vocabulary.com

Vocabulary lists containing decimal

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

What mattered was mostly the initial integer, or what was “to the left of the decimal point,” rather than anything more exact.

From MarketWatch Jun. 17, 2026

According to Fodor, the new work confirms the Standard Model to 11 decimal places and significantly narrows the chances that unknown physics is hiding in this particular measurement.

From Science Daily May 19, 2026

Sharp, who worked at the Greenwich Royal Observatory and has a crater on the moon named after him, was also a mathematician who calculated pi to 72 decimal places.

From BBC Apr. 1, 2026

“My usual rule of thumb is, move the decimal point one place to the left,” Matheson said.

From Los Angeles Times Feb. 24, 2026

Because every fifteen minutes, the animated ceiling looped through call numbers for every Dewey decimal room in the library.

From "Escape from Mr. Lemoncello's Library" by Chris Grabenstein

Despite leaving school at a young age and initially finding terms like "decimals" and "algebra" intimidating, Mr Elsom is said to have quite a talent for working with figures.

From BBC Aug. 11, 2025

The leaders of those and other rate stats — expressed with decimals — are now sprinkled with Negro League standouts.

From Los Angeles Times May 29, 2024

Eventually she leads us toward more abstract concepts such as the polar coordinate system, a graphical approach to defining a point using distance and angle, as well as irrational numbers and decimals that repeat infinitely.

From Scientific American Jun. 20, 2023

Since decimals are forms of fractions, locating decimals on the number line is similar to locating fractions on the number line.

From Textbooks May 6, 2020

Understanding fractions, and decimals, and percentages, and even geometry—all that was practical.

From "Speak" by Laurie Halse Anderson

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