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Synonyms

formidable

American  
[fawr-mi-duh-buhl, fawr-mid-uh-buhl] / ˈfɔr mɪ də bəl, ˌfɔrˈmɪd ə bəl /

adjective

  1. causing fear, apprehension, or dread.

    a formidable opponent.

    Synonyms:
    horrible, frightful, fearful, menacing, threatening, appalling, dreadful
    Antonyms:
    pleasant
  2. of discouraging or awesome strength, size, difficulty, etc.; intimidating.

    a formidable problem.

  3. arousing feelings of awe or admiration because of grandeur, strength, etc.

  4. of great strength; forceful; powerful.

    formidable opposition to the proposal.


formidable British  
/ ˈfɔːmɪdəbəl /

adjective

  1. arousing or likely to inspire fear or dread

  2. extremely difficult to defeat, overcome, manage, etc

    a formidable problem

  3. tending to inspire awe or admiration because of great size, strength, excellence, etc

"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

  • formidability noun
  • formidableness noun
  • formidably adverb
  • nonformidability noun
  • nonformidable adjective
  • nonformidableness noun
  • nonformidably adverb
  • quasi-formidable adjective
  • quasi-formidably adverb
  • superformidable adjective
  • superformidableness noun
  • superformidably adverb
  • unformidable adjective
  • unformidableness noun
  • unformidably adverb

Etymology

Origin of formidable

First recorded in 1400–50; late Middle English, from French, from Latin formīdābilis “causing fear,” from formīd(āre) “to fear” + -ābilis -able

Explanation

People who are formidable inspire fear and respect thanks to their size, or special ability, or unusual qualities. If you're a wildly popular celebrity, you probably don't go anywhere without a formidable bodyguard. What's interesting about formidable is that we often tend to use it about things that are simultaneously scary and impressive. A formidable opponent is almost by definition a worthy one; a formidable challenge is almost by definition one worth rising to. Not surprisingly, this word is derived from the Latin formidare, "to fear."

Keep Reading on Vocabulary.com

Vocabulary lists containing formidable

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.

That is formidable, but this book is meant to be definitive, and it succeeds in accomplishing that.

From Salon • Apr. 14, 2026

Former Arsenal duo Lee Dixon and David Seaman were part of a formidable backline for the Gunners during the 1990s and early 2000s - and both also featured for England.

From BBC • Apr. 10, 2026

His most formidable obstacles to another comeback might be physical.

From Los Angeles Times • Apr. 8, 2026

It obviously has a formidable track record of upending consumer categories.

From The Wall Street Journal • Apr. 4, 2026

Jesus’ possession of only a few research students appeared related to its formidable reputation on the river.

From "Double Helix" by James D. Watson