SKIP TO CONTENT

decimal

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.

Definitions of decimal
  1. noun
    a number in the decimal system
    see moresee less
    type of:
    number
    a concept of quantity involving zero and units
  2. adjective
    numbered or proceeding by tens; based on ten
    “the decimal system”
    synonyms: denary
    quantitative
    expressible as a quantity or relating to or susceptible of measurement
  3. noun
    a proper fraction whose denominator is a power of 10
    synonyms: decimal fraction
    see moresee less
    types:
    circulating decimal, recurring decimal, repeating decimal
    a decimal with a sequence of digits that repeats itself indefinitely
    type of:
    proper fraction
    a fraction with a numerator smaller than the denominator
Word Family
EDITOR’S CHOICE

Test prep from the experts

Boost your test score with programs developed by Vocabulary.com’s experts.

  • Proven methods: Learn faster, remember longer with our scientific approach.
  • Personalized plan: We customize your experience to maximize your learning.
  • Strategic studying: Focus on the words that are most crucial for success.

SAT/PSAT

$29.95
  • Number of words: 500+
  • Duration: 8 weeks or less
  • Time: 1 hour / week

TOEFL

$29.95
  • Number of words: 500+
  • Duration: 10 weeks or less
  • Time: 1 hour / week

ACT

$29.95
  • Number of words: 700+
  • Duration: 10 weeks
  • Time: 1 hour / week