fundamental vs least

fundamental

noun
  • The lowest partial of a complex tone. 

  • The lowest frequency of a periodic waveform. 

  • A main or major principle, rule, law, etc. which serves as the foundation or basis of a system; an essential part 

adj
  • Related to a foundation. base, or basis; serving as a foundation. 

  • essential; extremely important 

least

noun
  • Something of the smallest possible extent; an indivisible unit. 

prep
  • At least. 

  • What a stupid white privileged POS I am! Least I call myself out. 

  • 2019 December, Justin Blackburn, The Bisexual Christian Suburban Failure Enlightening Bipolar Blues, page 79 

det
  • The most little; the smallest amount or quantity of something. 

adv
  • Used for forming superlatives of adjectives, especially those that do not form the superlative by adding -est. 

  • In the smallest or lowest degree; in a degree below all others. 

How often have the words fundamental and least occurred in a corpus of books? (source: Google Ngram Viewer )