Meaning of FUNDAMENTAL in English

noun a leading or primary principle, rule, law, or article, which serves as the groundwork of a system; essential part, as, the fundamentals of the christian faith.

2. fundamental ·adj pertaining to the foundation or basis; serving for the foundation. hence: essential, as an element, principle, or law; important; original; elementary; as, a fundamental truth; a fundamental axiom.

Webster English vocab.      Английский словарь Webster.