least vs least possible

least

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. 

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

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

least possible

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