infinity

noun in·fin·i·ty \ in-ˈfi-nə-tē \
Updated on: 17 Nov 2017

Definition of infinity

plural infinities
1 a :the quality of being infinite
b :unlimited extent of time, space, or quantity :boundlessness
2 :an indefinitely great number or amount
  • an infinity of stars
3 a :the limit of the value of a function or variable when it tends to become numerically larger than any preassigned finite number
b :a part of a geometric magnitude that lies beyond any part whose distance from a given reference position is finite
  • do parallel lines ever meet if they extend to infinity
c :a transfinite number (such as aleph-null)
4 :a distance so great that the rays of light from a point source at that distance may be regarded as parallel

Examples of infinity in a Sentence

  1. The view tapers off into infinity.

  2. a series of numbers that continues to infinity

  3. The night sky was filled with an infinity of stars.

Recent Examples of infinity from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'infinity.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of infinity

14th century

Other Mathematics and Statistics Terms


INFINITY Defined for English Language Learners

infinity

noun

Definition of infinity for English Language Learners

  • : the quality of having no limits or end : the quality of being infinite

  • : a space, amount, or period of time that has no limits or end

  • : a very great number or amount


INFINITY Defined for Kids

infinity

noun in·fin·i·ty \ in-ˈfi-nə-tē \

Definition of infinity for Students

plural infinities
1 :the quality of being without limits
  • the infinity of space
2 :a space, quantity, or period of time that is without limit


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