least -- (something that is of no importance; "it is the least I can do"; "that is the least of my concerns")
Overview of adj least
The adj least has 1 sense
least -- (the superlative of `little' that can be used with mass nouns and is usually preceded by `the'; a quantifier meaning smallest in amount or extent or degree; "didn't care the least bit"; "he has the least talent of anyone")
Overview of adv least
The adv least has 1 sense
least, to the lowest degree -- (used to form the superlative; "The garter snake is the least dangerous snake")