Definition

1. Adjective:

   • Four times as great or many: Describing something that is multiplied by four in quantity, size, or degree.
   • Having four units or components: Consisting of four parts, elements, or members.

2. Noun:

   • A quantity that is four times as great as another: A number or amount that is the product of multiplying something by four.
   • A set of four similar things considered as a unit: A group of four items regarded as a single entity.

3. Verb:

   • To increase fourfold: To become four times as great or to multiply something by four.

Examples of Usage

• Adjective:

  • The company reported a quadruple profit compared to last year.
  • The engine features a quadruple exhaust system.

• Noun:

  • Twenty is the quadruple of five.
  • She won a quadruple of major championships in a single season.

• Verb:

  • The town's population has quadrupled in the last two decades.
  • If you quadruple the recipe, you'll need four cups of flour instead of one.

Advanced Usage

• In mathematics and statistics: Used to describe a multiplicative relationship.
  • The effect was measured as a quadruple interaction between the variables.
• In sports and competitions: Referring to winning four major titles or achievements.
  • The athlete is chasing an unprecedented quadruple this year.

Variants and Related Words

• Quadruply (adverb): In a fourfold manner; by four times.
  • The risk is quadruply higher in that demographic.
• Quadruplet (noun): One of four children born at one birth.
  • The couple welcomed quadruplets.
• Quadruplex (adjective/noun): A specific technical term for something having four parts, such as a quadruplex telegraph system or cable.

Synonyms

• Fourfold: Consisting of four parts or being four times as much.
• Quadruplex: Having four components (used in specific technical contexts).

Related Phrases

• Quadruple alliance: A historical or political alliance between four nations or parties.
• Quadruple bypass: A surgical procedure involving four coronary arteries.
• Quadruple double: A basketball achievement where a player records double digits in four statistical categories in a single game.

Notes on Different Meanings

• The adjectival and nominal meanings are closely related, both centering on the number four. The verbal meaning is a dynamic process of achieving that fourfold state.
• In music, "quadruple" can describe meter (e.g., quadruple time), meaning there are four beats per measure.

Adjective

1. four times as great or many
   • a fourfold increase in the dosage
2. having four units or components
   • quadruple rhythm has four beats per measure
   • quadruplex wire

Noun

1. a quantity that is four times as great as another
2. a set of four similar things considered as a unit

Verb

1. increase fourfold
   • His stock earning quadrupled