Meaning of LEAST in English

LEAST

[least] adj, superlative of [1]little [ME leest, fr. OE laest, superl. of laessa less] (bef. 12c) 1: lowest in importance or position

2. a: smallest in size or degree b: being a member of a kind distinguished by diminutive size "~ bittern" c: smallest possible: slightest

[2]least n (12c): one that is least -- at least 1: at the minimum

2: in any case [3]least adv, superlative of

[2]little (13c): in the smallest or lowest degree -- least of all : especially not "no one, least of all the children, paid attention"

Merriam-Webster English vocab.      Английский словарь Merriam Webster.