Of, or relating to a foundation or foundations(adjective)
Fundamental or underlying(adjective)
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Use "foundational" in a sentence
"Going forward, we are looking at a few key areas for investment in Afghanistan, what we call our "foundational investments.""
"Once all of these elements are in place however, if you are still lost in the blahs it is time for what I call the foundational questions."
"Furthermore, it was clear to Ruvu people that although aspects of their episteme were rooted in foundational knowledge inherited from earlier ancestors, they were still required to recreate ideologies and temporal sociocultural institutions continuously to satisfy the demands of spirit forces and to meet the needs arising from their temporal contexts."