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Synonyms

fortify

American  
[fawr-tuh-fahy] / ˈfɔr təˌfaɪ /

verb (used with object)

fortified, fortifying
  1. to protect or strengthen against attack; surround or provide with defensive military works.

  2. to furnish with a means of resisting force or standing strain or wear.

    to fortify cotton with nylon.

  3. to make strong; impart strength or vigor to.

    to fortify oneself with a good breakfast.

    Synonyms:
    reinforce, strengthen
  4. to increase the effectiveness of, as by additional ingredients.

    to fortify a diet with vitamins; to fortify a lotion with lanolin.

  5. to strengthen mentally or morally.

    to be fortified by religious faith.

    Synonyms:
    embolden, hearten
  6. to confirm or corroborate.

    to fortify an accusation with facts.

  7. Nutrition. to add one or more ingredients to (a food) to increase its nutritional content.

  8. to add alcohol to (wine or the like).


verb (used without object)

fortified, fortifying
  1. to set up defensive works; erect fortifications.

fortify British  
/ ˈfɔːtɪˌfaɪ /

verb

  1. (also intr) to make (a place) defensible, as by building walls, digging trenches, etc

  2. to strengthen physically, mentally, or morally

  3. to strengthen, support, or reinforce (a garment, structure, etc)

  4. to add spirits or alcohol to (wine), in order to produce sherry, port, etc

  5. to increase the nutritious value of (a food), as by adding vitamins and minerals

  6. to support or confirm

    to fortify an argument with facts

"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

  • fortifiable adjective
  • fortifier noun
  • fortifyingly adverb
  • nonfortifiable adjective
  • nonfortifying adjective
  • refortify verb (used with object)
  • underfortify verb (used with object)
  • unfortifiable adjective

Etymology

Origin of fortify

First recorded in 1400–50; late Middle English fortifien, from Middle French fortifier, from Late Latin fortificāre, equivalent to Latin forti(s) “strong” + -ficāre -fy

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.

Defense Secretary Pete Hegseth, who visited troops in the Middle East over the weekend, said the U.S. military took steps to fortify and disperse forces at its bases in the region before strikes began.

From The Wall Street Journal • Apr. 1, 2026

He says he persuaded European partners to provide funding to help Poland fortify his borders.

From Barron's • Mar. 13, 2026

After a bruising property downturn and years of economic uncertainty, families appear determined to fortify their balance sheets first — and spend later.

From MarketWatch • Feb. 26, 2026

New software techniques and extensions need to be developed to detect and fortify quantum programs against security threats.

From Science Daily • Jan. 20, 2026

He ate a quick breakfast to fortify himself before venturing down the hill to Handsome’s field where the musk ox stood sleeping next to the reflection pond.

From "The Very, Very Far North" by Dan Bar-el