fondamental

Fondamental is an adjective used in French (masculine fondamental, feminine fondamentale) to denote something essential, basic, or underlying. It derives from Medieval Latin fundamentum and is a direct cognate of the English word fundamental.

In French, fondamental appears in many technical and academic expressions, such as principe fondamental, loi fondamentale, and théorème fondamental. In music, one may encounter the term note fondamental or fréquence fondamental, referring to the fundamental pitch or frequency as opposed to overtones. In philosophy, science, and mathematics, fondamental concepts or questions are those regarded as foundational to a theory or field.

In English-language contexts, the exact form fondamental is uncommon; the standard term is fundamental. Because of its use in French and in translations, fondamental may appear when quoting French sources or discussing French terminology. The word also appears in other Romance languages in equivalent forms (for example, fondamental in some academic borrowings or translations).

See also terms related to base and basis, such as foundation, fundament, and foundational concepts. The nuance of fondamental tends to emphasize an underlying, essential base, whereas in English the parallel term foundational highlights the role of providing a base for further development.