a small knob or disc secured to an article, e.g. of clothing, and used as a fastener by passing it through a buttonhole or loop
chiefly NAmer a usu circular badge bearing a design or slogan
a knob on an item of electrical or electronic equipment that is pressed to activate a function
a guard on the tip of a fencing foil
something of little value
not worth a button
hit the right button
to say or do something that meets with approval
on the button
informal with absolute precision; exactly
buttonless adj
[Middle English boton from Old French bouton, of Germanic origin]