Meaning of LEAST in English
[least] adj, superlative of 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
least n (12c): one that is least -- at least 1: at the minimum
2: in any case least adv, superlative of
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. 2012