slide rule

American  

noun

1. a device for performing mathematical calculations, consisting essentially of a ruler having a sliding piece moving along it, both marked with graduated, usually logarithmic, scales: now largely replaced by the electronic calculator.

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slide rule British  

noun

1. a mechanical calculating device consisting of two strips, one sliding along a central groove in the other, each strip graduated in two or more logarithmic scales of numbers, trigonometric functions, etc. It employs the same principles as logarithm tables

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Etymology

Origin of slide rule

1655–65 for earlier sense; 1875–80 for current sense

Example Sentences

As MarketWatch has recently written, hedge-fund manager Harris “Kuppy” Kupperman, among others, has already run a slide rule over the math of the AI mania and found it comes up short.

From MarketWatch • Nov. 14, 2025

With an abacus and a slide rule, earlier helpmeets, you had to know something of the mathematical process.

From Washington Post • Apr. 28, 2023

He had a knack for math—“I used to do slide rule speed competitions,” he confesses—and majored in physics at Texas A&M University, College Station.

From Science Magazine • Jul. 27, 2022

For that exam, he said, he brought a slide rule with him.

From BBC • Jun. 24, 2022

When Werner asks for a slide rule, the professor slips one onto the desk immediately, having expected the request.

From "All the Light We Cannot See" by Anthony Doerr