Fundamental interaction

What is Fundamental interaction?

Fundamental interaction definition and meaning on Dictionary terms:
serving as, or being an essential part of, a foundation or basis; basic; underlying: fundamental principles; the fundamental structure.
of, relating to, or affecting the foundation or basis: a fundamental revision.
being an original or primary source: a fundamental idea.
Music. (of a chord) having its root as its lowest note.

a basic principle, rule, law, or the like, that serves as the groundwork of a system; essential part: to master the fundamentals of a trade.
Also called fundamental note, fundamental tone. Music. the root of a chord.the generator of a series of harmonics.

Physics. the component of lowest frequency in a composite wave.