adjective
superlative form of 1little
smallest in amount or degree
not (in) the least bit
take/follow the path/line of least resistance
noun
the least
something of the lowest importance, strength, value, etc.
at least
not less than a specified amount, level, etc.
used to say that something (such as a bad situation) could be or have been worse
used to indicate the smallest or easiest thing that someone can or should do
a - used to indicate that the truth of a statement might change or has changed
b - used to indicate that the truth of a previous statement is not certain
at the (very) least
used to indicate the least thing that is true, acceptable, desirable, or certain to happen
not (in) the least
not at all :not in any way or respect
the least (someone) can do
the smallest or easiest thing that someone can or should do
to say the least
used to emphasize a statement
adverb
superlative form of 2little
in or to the smallest degree
last but not least
least of all
especially not
not least
formal :especially or particularly