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.

China’s “microelectronics, their motors, their rare earth, their magnets—which is foundational to robotics—they are the world’s best,” Huang said in a podcast in March.

From The Wall Street Journal • Apr. 3, 2026

Donald Trump’s executive order to promote AI in schools argued that the tech “sparks curiosity and creativity” and “will equip our students with the foundational knowledge and skills.”

From Salon • Mar. 30, 2026

The researchers see it as a foundational design that could eventually be developed into practical tools for clinical and laboratory use.

From Science Daily • Mar. 25, 2026

As the history of absentee voting during the Civil War era shows, states have long permitted post–Election Day receipt of absentee ballots to safeguard voting rights and protect our foundational democratic principles.

From Slate • Mar. 13, 2026

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

From "Fablehaven" by Brandon Mull

foundational

Example Sentences

Related Words