least least /ˈliːst/

adjective

1. () The superlative of 'little' that can be used with mass nouns and is usually preceded by 'the'; a quantifier meaning smallest in amount, extent or degree  ( least )
   the superlative of 'little' that can be used with mass nouns and is usually preceded by 'the'; a quantifier meaning smallest in amount, extent or degree
    Didn't care the least bit
   didn't care the least bit
    He has the least talent of anyone
   he has the least talent of anyone
   

adverb

1. () Used to form the superlative  ( to the lowest degree , least )
   used to form the superlative
    The garter snake is the least dangerous snake
   The garter snake is the least dangerous snake
   

noun

1. Something that is of no importance  ( least )
   something that is of no importance
    It is the least I can do
   it is the least I can do
    That is the least of my concerns
   that is the least of my concerns