noun re·dun·dan·cy \ri-ˈdən-dən(t)-sē\

Definition of redundancy



  1. 1 a :  the quality or state of being redundant :  superfluity b :  the use of redundant components; also :  such components c chiefly British :  dismissal from a job especially by layoff

  2. 2 :  profusion, abundance

  3. 3 a :  superfluous repetition :  prolixity b :  an act or instance of needless repetition

  4. 4 :  the part of a message that can be eliminated without loss of essential information

Examples of redundancy in a sentence

  1. Avoid redundancy in your writing.

  2. Try to avoid using redundancies in your writing.

  3. The design incorporates several redundancies.

  4. a system with a high level of redundancy

  5. The restructuring is expected to result in the redundancy of several hundred workers.

  6. The workers are now facing redundancy.

Did You Know?

Redundancy, closely related to redound, has stayed close to the original meaning of "overflow" or "more than necessary". Avoiding redundancy is one of the prime rules of good writing. ""In the modern world of today" contains a redundancy; so does "He died of fatal wounds" and "For the mutual benefit of both parties". But redundancy doesn't just occur in language. "Data redundancy" means keeping the same computer data in more than one place as a safety measure, and a backup system in an airplane may provide redundancy, again for the sake of safety.

Circa 1602

First Known Use of redundancy

circa 1602

Other Aeronautics/Aerospace Terms

REDUNDANCY Defined for English Language Learners


noun re·dun·dan·cy \ri-ˈdən-dən(t)-sē\

Definition of redundancy for English Language Learners

  • : the act of using a word, phrase, etc., that repeats something else and is therefore unnecessary

  • : a word, phrase, etc., that repeats something else and is therefore unnecessary : a redundant word, phrase, etc.

  • : a part in a machine, system, etc., that has the same function as another part and that exists so that the entire machine, system, etc., will not fail if the main part fails

Seen and Heard

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of, relating to, or resembling a fox

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