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Medical Dictionary

cold sore

noun

Medical Definition of cold sore

  1. :  a vesicular lesion that typically occurs in or around the mouth, that initially causes pain, burning, or itching before bursting and crusting over, and that is caused by a herpes simplex virus which remains dormant in the body and may be reactivated by a variety of factors (as stress, fever, or sunburn)—called also fever blister; compare canker sore




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