least vs maximal

least

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

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 

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. 

maximal

adj
  • Largest, greatest (in magnitude), highest, most. 

noun
  • Said of a set of well-formed formulas: that it is as large as it can be without being inconsistent; i.e. that for any well-formed formula φ, the set contains either φ or ~φ. 

  • The element of a set with the greatest magnitude. 

  • Said of an ideal of a ring or a filter of a lattice: that it is as large as it can be without being trivial (improper). 

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