fundamental adj
1: serving as an essential component; "a cardinal rule"; "the central cause of the problem"; "an example that was fundamental to the argument"; "computers are fundamental to modern industrial structure" [syn: cardinal, central, key, primal]
2: being or involving basic facts or principles; "the fundamental laws of the universe"; "a fundamental incompatibility between them"; "these rudimentary truths"; "underlying principles" [syn: rudimentary, underlying]
3: far-reaching and thoroughgoing in effect especially on the nature of something; "the fundamental revolution in human values that has occurred"; "the book underwent fundamental changes"; "committed the fundamental error of confusing spending with extravagance"; "profound social changes" [syn: profound] n : the lowest tone of a harmonic series [syn: [[fundamental frequency]], first harmonic]