bouton /bo̅o̅tôN″, bo̅o̅″ton/ [Fr, button] , 1. a button, pustule, or knoblike swelling, such as the expanded end of an axon at a synapse (terminaux) that comes into contact with cell bodies of other neurons. 2. a lesion associated with cutaneous leishmaniasis. 3. a small abscess of the intestinal mucosa in amebic dysentery.
