| Main Entry: | |
| Part of Speech: | noun |
| Definition: | mouth ulcer |
| Synonyms: | canker, cold sore, fever blister, herpes labialis, herpes simplex, lesion, oral herpes |
| Notes: | a canker sore is inside the mouth while a cold sore is outside the mouth a cold sore or fever blister is usually caused by herpes simplex; a canker sore is usually due to food allergy or stress |
| Main Entry: | fever blister |
| Part of Speech: | noun |
| Definition: | cold sore |
| Synonyms: | blister, bulla, herpes labialis, herpes simplex lesion, oral herpes, vesicle |
| Notes: | a cold sore or fever blister is usually caused by herpes simplex; a canker sore is usually due to food allergy or stress |