Definition of "Fundamental" :

noun: the lowest tone of a harmonic series

noun: any factor that could be considered important to the understanding of a particular business

"Fundamentals include a company's growth, revenues, earnings, management, and capital structure."

adjective: serving as an essential component

"An example that was fundamental to the argument."

adjective: being or involving basic facts or principles

"The fundamental laws of the universe."

adjective: far-reaching and thoroughgoing in effect especially on the nature of something

"The fundamental revolution in human values that has occurred."