Definition

1. Noun:
   • The quality or state of being circular: The condition of having the shape of a circle or being arranged in a circle.
   • A statement or argument that is circular: In logic and reasoning, a form of faulty reasoning where the conclusion is assumed in one of the premises, resulting in an argument that goes in a circle and proves nothing.

Examples of Usage

• Noun (Physical Shape):

  • The circularity of the ancient stone ring was perfect.
  • Engineers measured the circularity of the newly machined gear.

• Noun (Logical Fallacy):

  • The philosopher pointed out the circularity in the argument: "We know the book is true because it says so, and we can trust what it says because it is true."
  • Avoid circularity in your essay; your conclusion should not simply restate your premise.

Advanced Usage

• "Vicious circularity": A particularly problematic or unbreakable circular argument.

  • The debate reached a point of vicious circularity, with neither side able to provide independent evidence.

• "Geometric circularity": Used in technical contexts to specify the roundness of an object as a measurable geometric property.

  • The tolerance for geometric circularity in this component is extremely high.

Variants and Related Words

• Circular (adj): Shaped like or moving in a circle. (e.g., )
• Circulate (verb): To move or cause to move continuously in a closed circuit or system. (e.g., )
• Circularly (adv): In a circular manner or pattern.

Synonyms

• Roundness: The quality of being round, especially in a physical sense.
• Tautology: In logic, a statement that is true by necessity or by virtue of its logical form, often overlapping with the concept of circular reasoning.

Related Phrases

• Circular reasoning: The logical fallacy synonymous with the second meaning of 'circularity'.
  • His entire thesis was dismissed due to its reliance on circular reasoning.
• A circular argument: An argument that suffers from circularity.
  • Defining "good art" as "art that is popular" and "popular art" as "art that is good" is a classic circular argument.

Related Idioms

• To go around in circles: To engage in a discussion or activity that makes no progress, often because of circularity in logic or action.
  • We're just going around in circles; we need new information to move this debate forward.

Noun

1. the roundness of a 2-dimensional figure