What is the meaning of fundamental?

noun

• Any factor that could be considered important to the understanding of a particular business.
  • usage: "fundamentals include a company's growth, revenues, earnings, management, and capital structure"
• The lowest tone of a harmonic series.
  • synonyms: fundamental frequency, first harmonic

adjective

• Serving as an essential component.
  • usage: "a cardinal rule"; "the central cause of the problem"; "an example that was fundamental to the argument"; "computers are fundamental to modern industrial structure"
  • synonyms: cardinal, central, key, primal
• Being or involving basic facts or principles.
  • usage: "the fundamental laws of the universe"; "a fundamental incomatibility between them"; "these rudimentary truths"; "underlying principles"
  • synonyms: rudimentary, underlying
• Far-reaching and thoroughgoing in effect especially on the nature of something.
  • usage: "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"
  • synonyms: profound