say it: fuhn-duh-MEN-tuhl
fundamental is an adjective and noun meaning "serving as an essential component". It carries 5 recorded senses.
being or involving basic facts or principles
“the fundamental laws of the universe”
“a fundamental incompatibility between them”
“these rudimentary truths”
“underlying principles”
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”
Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.
Definitions, synonyms and semantic relations for fundamental come from Princeton University’s WordNet. The pronunciation comes from the CMU Pronouncing Dictionary. Commonness is measured against a corpus of everyday English. Full sources and licences.