foundational

adjective

foun·​da·​tion·​al fau̇n-ˈdā-sh(ə-)nəl 

: of, relating to, or forming or serving as a base or foundation : fundamental

foundational principles/doctrines

These foundational volumes proved to be, each in its own way, enabling gestures for the growth of sophisticated theories and critical practices in African, Caribbean, and African American literatures.

—Henry Louis Gates, Jr.

Property was, in a sense, foundational to culture, since English political economy rested on the private ownership of land, and the political economy, in turn, largely structured social relations.

—Jill Lepore

Philosophy is a foundational discipline. Not only does it do the spadework that makes the construction of other disciplines possible; it also pays constant attention to the foundations of those disciplines as they are practiced.

—Cognitive Science

foundationally adverb

Examples of foundational in a Sentence

Recent Examples on the Web

Since 2000, electricity has become even more central to daily life in most of the world, while its foundational importance to the most dynamic sectors in global markets can hardly be doubted. —Scott Montgomery, Forbes.com, 30 Jan. 2026

The Reader’s nonprofit board and foundational partners sought help from Noisy Creek, an upstart publisher bucking the trends and betting on the future of alt-weeklies. —Robert Channick, Chicago Tribune, 30 Jan. 2026

According to Variety, the feature slated to premiere on the streamer on March 20 was directed by Ben Feldman (Rich & Shameless) and focuses on the group’s early, foundational years and the influence of founding guitarist Hillel Slovak. —Gil Kaufman, Billboard, 30 Jan. 2026

While the Pelicans are focused on building a future around 2025 first-round picks Jeremiah Fears and Derik Queen, there’s still belief around the team that Murphy, Jones and Williamson can be foundational pieces of the puzzle moving forward. —Sam Amick, New York Times, 30 Jan. 2026

Word History

First Known Use

1657, in the meaning defined above

Rhymes for foundational

• formational
• gestational
• gradational
• locational
• mutational
• nonrational
• notational
• relational
• rotational
• sensational
• translational
• vibrational