1. An infectious disease, especially of children, characterized by a sudden occurrence of fever, loss of appetite, and throat ulcerations, caused by a Coxsackie virus.
2. Also called mouth blisters, it is the name of a painful mouth infection caused by coxsackieviruses.
3. A medical-dictionary definition: An acute infectious disease caused by either group A or group B coxsackievirus or by echoviruses, chiefly affecting young children in the summer; characteristics include vesiculoulcerative lesions on the mucous membranes of the throat, dysphagia, vomiting, and fever. (Does this provide a better understanding for you?)