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Synonyms

infeasible

American  
[in-fee-zuh-buhl] / ɪnˈfi zə bəl /

adjective

  1. not feasible; impracticable.


infeasible British  
/ ɪnˈfiːzəbəl /

adjective

  1. a less common word for impracticable

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms


Etymology

Origin of infeasible

First recorded in 1525–35; in- 3 + feasible


Explanation

Infeasible things are impossible, or too complicated to actually be done. Your idea of staging a city-wide game of Capture the Flag is probably infeasible. After several frustrating attempts at walking your cat around the neighborhood on a leash, you might finally decide the idea is infeasible — it's just not going to work the way you imagined. When something is feasible, it's entirely possible. Feasible comes from the Old French faisable, "that may be done," from the Latin root facere, "to make or do." When you add the "not" prefix in-, you get infeasible.

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

And coal would likely remain part of the energy mix for decades, with the need for baseload power and dependence on imports making a full phase-out infeasible before "the mid-2050s".

From Barron's ● Nov. 5, 2026

The Environment Agency told the Cunliffe Review that "the treatment costs of meeting 'good' may render the new reservoirs infeasible".

From BBC ● Aug. 29, 2026

Instead, they said that market and financial conditions had changed, rendering the plans infeasible, according to a letter sent by Ofland’s attorney to the city of Twentynine Palms last week.

From Los Angeles Times ● Apr. 30, 2026

The FDA already requires randomized controlled trials prior to approving vaccines and most medicines—except when they would be unethical or infeasible, as is the case for rare diseases and terminal cancers.

From The Wall Street Journal ● Dec. 3, 2025

"It does not seem infeasible," Professor Bernardi admitted tightly.

From Collector's Item by Evelyn E. Smith

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