for·ti·fy | \ˈfȯr-tə-ˌfī \
fortified; fortifying

Definition of fortify 

transitive verb

: to make strong: such as

a : to strengthen and secure (a place, such as a town) by forts or batteries a city fortified by high walls

b : to give physical strength, courage, or endurance to fortified by a hearty meal

c : to add mental or moral strength to : encourage fortified by prayer fortified by early successes

d : to add material to for strengthening or enriching fortified milk

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Other Words from fortify

fortifier \ˈfȯr-tə-ˌfī(-ə)r \ noun

Synonyms & Antonyms for fortify


harden, indurate, inure, season, steel, strengthen, toughen



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Did You Know?

Medieval cities were fortified against attack by high walls, and volunteers may fortify a levee against an overflowing river by means of sandbags. Foods can be fortified by adding vitamins, but "fortified wines", such as sherry and port, have brandy (a "stronger" drink) rather than vitamins added to them. By adopting good exercise habits, you can fortify your body against illness. And fortifying needn't always be physical. An author's reputation may be fortified by the success of his new book, or a prosecutor can fortify a case against a suspect by finding more evidence.

Examples of fortify in a Sentence

fortify a city against attack a city fortified by high walls Support for his theories has been fortified by the results of these experiments. He took a deep breath to fortify himself before stepping onto the stage. milk fortified with vitamin D
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Recent Examples on the Web

More than two miles inside the cave, where they are being fortified with high-protein gels and foil warming blankets, the boys have been practicing wearing diving masks and breathing under the instructions of the Seals. George Styllis,, "Rescue mission seeking to free trapped Thai soccer team may face danger from weekend storms," 6 July 2018 And for a majority of the public, such scandals only fortify their preexisting disapproval of the president. Eric Levitz, Daily Intelligencer, "Here’s Why Trump’s Approval Rating Has Gone Up," 16 May 2018 That area of the border, which Trump wants to fortify with a new wall, was already among the stretches best defended by the Americans. Nicholas Kulish,, "Desperation led migrant to face perils, and price, of smuggling," 1 July 2018 Sources of vitamin D include exposure to the sun, fatty fish such as salmon and trout, foods such as milk and orange juice fortified with the vitamin and dietary supplements. Laurie Mcginley, ajc, "Higher vitamin D levels linked to lower colorectal cancer risk, study finds," 14 June 2018 Measuring the extent of malnutrition is critical both for getting aid money and for deciding which children are in need of emergency medical treatment and therapeutic foods – often energy-dense pastes fortified with micronutrients. Emily Matchar, Smithsonian, "Can AI Tell If a Child Is Malnourished?," 8 June 2018 High school students have spent their entire educational lives participating in lockdown drills and walking into schoolhouse doors fortified with bulletproof glass. Katie Zezima, Washington Post, "‘I was not one bit surprised that it happened.’ Shock over school shootings has turned to numbness.," 19 May 2018 Curry, who also trains K-9 units, said handlers and their dogs often form an inseparable bond that's only fortified over time. Perry Vandell, azcentral, "ADOT to use K-9 units to detect drugs, human trafficking on major Arizona highways," 7 July 2018 But Chinese efforts to expand and fortify those reefs have been matched by diplomatic victories. The Economist, "Xi’s world order: July 2024," 7 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'fortify.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of fortify

15th century, in the meaning defined at transitive sense

History and Etymology for fortify

Middle English fortifien, from Anglo-French fortifier, from Late Latin fortificare, from Latin fortis strong

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Statistics for fortify

Last Updated

8 Oct 2018

Look-up Popularity

Time Traveler for fortify

The first known use of fortify was in the 15th century

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More Definitions for fortify



English Language Learners Definition of fortify

: to strengthen (a place) by building military defenses (such as walls, trenches, etc.)

: to make (someone or something) stronger

: to make (yourself) feel stronger or less fearful


for·ti·fy | \ˈfȯr-tə-ˌfī \
fortified; fortifying

Kids Definition of fortify

1 : to make strong Walls fortified the city against attack. Calcium fortifies bones.

2 : to add material to (something) to strengthen or improve it The cereal was fortified with vitamins.

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Comments on fortify

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