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slide rule

slide rule

5 8.5
A long thin tool with sliding scales that people use to do quick math before calculators
  • noun
  • /slaɪd ruːl/
  • Archaic
translation icon : regla de cálculo
  • I am of the generation that can still operate a slide rule—for what purpose I can only scarcely remember.
  • use a slide rule

And I grew up basically in the geekosphere and I even know I may be the last generation of those officially trained on how to use a slide rule.

Examples

  • Before electronic calculators, engineers relied on a slide rule for complex calculations.

  • I could show you how to read a slide rule.

  • I used a slide rule in college.

    Academic text (2000)
  • I remember when we had things called "slide rules" to do mathematical operations.

    Blog text (19)
  • Of course, he needed a pencil, paper, a drafting board, and a slide rule.

    Academic text (2006)
  • Amazing, because back then they did all the engineering with slide rules and drafting instruments—no computers!

    Blog text (34)
  • Everything was neat and tidy: sharpened pencils, rubber bands, thumbtacks, blank notepads, an ancient slide rule.

    Fiction book (2001)
  • He demonstrated how to quickly solve equations using the slide rule in his math class.

  • In the past, students often practiced their arithmetic skills with a slide rule instead of a calculator.

Synonyms

pocket calculator
vsslide rule
1 2.1

A small electronic device you can hold or carry in a pocket to do math

is analog and depends on moving scales rather than electric components
calculating machine
vsslide rule
  • Archaic
1 5.9

A machine for doing math, often mechanical or early electronic

is narrower, referring to the specific analog sliding instrument used for calculations
slipstick
vsslide rule
  • Archaic
9.9

A tool you use by hand to do quick math by moving marked scales

is the typical analog sliding instrument used before electronic calculators
minicalculator
vsslide rule
  • Archaic
8.3

A very small handheld electronic device for doing simple math

is analog and works by sliding graduated scales rather than electronic parts
hand calculator
vsslide rule
2.1

A small electronic device you hold in your hand to do math

is analog and uses sliding scales for calculation instead of electronic circuitry

How Complex

computer
  • Archaic
495 9.5
calculating machine
  • Archaic
1 5.9
calculator
81 1.3
slide rule
  • Archaic
5 8.5
reckoner
  • Archaic
9.0

Surface Forms

slide rule singular
slide rules plural

Morphology

slide + rule

The noun 'slide rule' is compositionally built from 'slide' (to move smoothly) and 'rule' (a straight-edged measuring tool), so a learner can infer it denotes a ruler-like tool that slides for calculation. This is a literal, cross-linguistically common construction (e.g. French 'règle à calcul', Spanish 'regla de cálculo'), making the meaning accessible to a B1 learner who knows the constituents.

Etymology

Slide rule comes from the tool's look and parts: a moving slide that fits inside a long rule, a kind of ruler, so scales with numbers can be lined up to 'calculate' quickly. That's why the name means a hand tool used for fast math before electronic calculators.