AT THE DROP OF A HAT

This exspression means,happening instantly without delay
phrase definition originates in the 19th century that time 
it was common to signal the begining of a fight or a race 
by either dropping a hat or sweeping it in rapid downward
motion examplee were all packed and ready to go we can leave at the drop of a hat
idoms with little provocation ,freely immeadately
on the slightest uring alludes to droppinging of a hat a signal 
if you do something at the drop of a hat you do it willing 
or without hesitation with slghtest provocation ready to argue at the drop of a hat
immeadately,without delay would sign the contract at the drop of a hat
at the drop of a hat phrase easily ,with little encouragement 
i hate to speak in public but she'll get on stage at the drop of a hat .