Definition of Pathognomonic Pathognomonic: A sign or symptom that is so characteristic of a disease that it can be used to make a diagnosis. For example, Koplik spots in the mouth opposite the first and second upper molars are pathognomonic of measles.
Pathognomonic: A sign or symptom that is so characteristic of a disease that it can be used to make a diagnosis. For example, Koplik spots in the mouth opposite the first and second upper molars are pathognomonic of measles.
