English definition of “least”
› less than anyone or anything else: Which car costs least? I chose the least expensive dish on the menu. No one, least of all (= especially not) James, is going to be angry with you.
at least › as much as, or more than, a number or amount: You'll have to wait at least an hour. › something that you say when you are telling someone about an advantage in a bad situation: It's a small house but at least there's a garden. › used to say that someone should give a small amount of help although they do not intend to give a lot: Even if you didn't want to send a present, you could at least have sent a card. › something that you say in order to correct something you said that was wrong: I've seen that film. At least, I saw the beginning then I fell asleep.
not least formal › especially: The whole trip was fascinating, not least because of the people I met.
not in the least › not at all: I don't mind staying at home, not in the least. → See also last but not least