Definition

Noun: * A mechanical analog computing device: A slide rule is a handheld instrument consisting of graduated scales, most often logarithmic, that slide against each other. It is used to perform mathematical calculations such as multiplication, division, roots, logarithms, and trigonometry through the mechanical alignment of these scales.

Examples of Usage

• Noun:
  • Before the invention of electronic calculators, engineers and scientists relied on a slide rule for complex calculations.
  • He still keeps his father's old slide rule on the desk as a reminder of a bygone technological era.
  • Operating a slide rule requires an understanding of logarithms and careful attention to the decimal point.

Advanced Usage

• "to use a slide rule": To perform calculations with this specific device.
  • Students in the 1960s were taught how to use a slide rule in their physics classes.
• The term can be used metaphorically to refer to outdated technology or methods.
  • In today's digital world, that software is about as useful as a slide rule.

Variants and Related Words

• Slipstick (n): An informal or slang term for a slide rule.
  • The veteran engineer affectionately called his calculating tool his slipstick.
• Cursor (n): On a slide rule, the clear component with a fine hairline that slides over the scales to aid in reading precise values.

Synonyms

• Analog calculator: A more descriptive technical synonym.
• Calculation rule: A less common general term.

Related Phrases

• Slide rule scale: Refers to any of the individual logarithmic or linear scales marked on the instrument (e.g., A scale, B scale, C scale, D scale).
  • The C and D scales on a standard slide rule are used for basic multiplication and division.

Noun

1. analog computer consisting of a handheld instrument used for rapid calculations; have been replaced by pocket calculators