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Definitions

foundational

[foun-dey-shuh-nl] / faʊnˈdeɪ ʃə nl /
ADJECTIVE
bottom
Synonyms
STRONG
base basement basic ground last primary radical underlying
WEAK
basal lowermost lowest meat-and-potatoes nethermost rock-bottom undermost
Antonyms
STRONG
secondary
WEAK
highest top
ADJECTIVE
elementary
Synonyms
STRONGEST
elemental fundamental rudimentary straightforward underlying
WEAK
ABCs abecedarian basal beginning child's play clear duck soup easy essential facile initial introductory meat and potatoes original plain prefatory preliminary primary primitive primo simplest simplex simplified substratal uncomplex uncomplicated
Antonyms
STRONGEST
additional advanced extra secondary
WEAK
abstruse complex complicated compound difficult hard intricate involved
ADJECTIVE
fundamental
Synonyms
STRONGEST
central constitutional crucial elemental elementary essential indispensable integral intrinsic major necessary paramount principal radical significant structural theoretical underlying vital
STRONG
bottom cardinal first key organic original primary prime primitive requisite supporting
WEAK
axiological axiomatic basal bottom-line constitutive grassroots meat-and-potatoes primordial rudimentary substratal substrative sustaining underived
Antonyms
STRONGEST
accessory auxiliary extrinsic inessential insignificant learned least lesser minor needless nonessential secondary trivial unimportant unnecessary
WEAK
additional advanced extra subordinate
ADJECTIVE
lowermost
Synonyms
WEAK
basal base basement basic ground last lowest meat-and-potatoes nethermost primary radical rock-bottom underlying undermost
ADJECTIVE
nethermost
Synonyms
WEAK
basal base basement basic deepest ground last lowermost lowest meat-and-potatoes primary radical rock-bottom underlying undermost
ADJECTIVE
primary/prime
Synonyms
WEAK
basal beginning bottom central elemental elementary essential first introductory meat-and-potatoes original primitive principal radical rudimentary simple three R's ultimate underivative underived underlying
Antonyms
WEAK
auxiliary latest least minor secondary supplemental
ADJECTIVE
radical
Synonyms
STRONGEST
profound
STRONG
basal bottom cardinal constitutional essential native natural organic original primary primitive
WEAK
deep-seated inherent innate intrinsic meat-and-potatoes primal thoroughgoing underlying vital
Antonyms
STRONG
inessential minor secondary unimportant
WEAK
extrinsic nonessential superficial
ADJECTIVE
rudimental
Synonyms
WEAK
ABCs abecedarian basal basic beginning child's play clear duck soup easy elemental essential facile fundamental initial introductory meat and potatoes original plain prefatory preliminary primary primitive primo rudimentary simplest simplex simplified straightforward substratal uncomplex uncomplicated underlying
ADJECTIVE
undermost
Synonyms
WEAK
basal base basement basic ground last lowermost lowest meat-and-potatoes nethermost primary radical rock-bottom underlying

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.

A few lines of explanation or context on a wall label can add perspective for even the most informed visitor, and provides crucial support to those with less foundational exposure and access to art.

From Los Angeles Times • Apr. 22, 2026

Prudential of Japan on Tuesday said the extension “reflects POJ’s determination that additional time is needed to complete foundational reforms to its compensation structure, governance, sales oversight, and broader operating model.”

From Barron's • Apr. 21, 2026

Abel added, “Our foundational values continue to be what we build our company through.”

From The Wall Street Journal • Apr. 18, 2026

"The 1949 act was really helpful and foundational but there was more to be done after that," says Kate.

From BBC • Apr. 18, 2026

“We would forfeit the protection afforded by the foundational covenants of the treaty.”

From "Fablehaven" by Brandon Mull