What is the meaning of Fundamental?

A main or major principle, rule, law, etc. which serves as the foundation or basis of a system; an essential part

The lowest frequency of a periodic waveform.

The lowest partial of a complex tone.

Related to a foundation, base, or basis; serving as a foundation.

Essential; extremely important.

basic, fundamental

fundamental

fundamental

fundamental, basic

fundamental, basic

fundamental; essential (pertaining to the basic part or notion of something)

fundamental

fundamental

fundamental

Source: wiktionary.org