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Definitions

foundation

[foun-dey-shuhn] / faʊnˈdeɪ ʃən /
NOUN
basis for something physical or mental
Synonyms
STRONGEST
authority base bedrock groundwork infrastructure support
STRONG
ABCs basics bed bottom foot footing ground guts heart justification nitty-gritty nub prop reason root setup stay substratum substructure understructure
WEAK
bottom line brass tacks nuts and bolts underpinning
Antonyms
STRONG
cowardice exterior exteriority fear outside top
NOUN
established institution
Synonyms
STRONGEST
association charity company corporation endowment establishment institute organization society
STRONG
guild inauguration plantation settlement trusteeship

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.

Indeed, if you’re listening to this on a screen reader, you’re enjoying digital accessibility, which was built on the foundation of usability for those with disabilities.

From Slate • Apr. 4, 2026

The experience helped the military refine tactics and procedures that have helped form the foundation of rescue operations since.

From BBC • Apr. 3, 2026

Instead of building everything from scratch, you’re layering onto a foundation that’s already there — salty, savory, complex.

From Salon • Apr. 3, 2026

“Manufacturers are entering the second quarter on a more fragile foundation as a result.”

From MarketWatch • Apr. 1, 2026

As they approached this gray foundation, Mrs. Frisby saw that near the middle of it, a few inches off the ground, there was a square patch of darker gray.

From "Mrs. Frisby and the Rats of NIMH" by Robert C. O'Brien

From Roget's 21st Century Thesaurus, Third Edition Copyright © 2013 by the Philip Lief Group.