number line

American  

noun

Mathematics.

1. a straight line on which there is indicated a one-to-one correspondence between points on the line and the set of real numbers.

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number line British  

noun

1. an infinite line on which points represent the real numbers

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Etymology

Origin of number line

First recorded in 1955–60

Example Sentences

For example, the number line is infinite, regardless of whether you start it at –∞, 0 or 1.

From Scientific American • Jul. 13, 2023

The rest of the numbers on the number line are irrational numbers.

From Scientific American • May 23, 2023

Even such bonkers-looking numbers, however, together with all the rational numbers, make up only a tiny fraction of the real numbers, or numbers that can appear along a number line.

From Scientific American • May 23, 2023

Notice that both 5 and –5 are 5 units from 0 on the number line.

From Textbooks • Sep. 23, 2020

But nowadays everybody knows that zero can’t really sit anywhere on the number line, because it has a definite numerical value of its own.

From "Zero: The Biography of a Dangerous Idea" by Charles Seife