least vs minimal

least

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

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. 

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 

minimal

noun
  • Something very small; a tiny part or fragment. 

adj
  • Characterised by the use of simple form or structures. 

  • Characterised by the repetition and gradual alteration of short phrases. 

  • The smallest possible amount, quantity, or degree. 

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