cold sore


Definition of cold sore

: a group of fluid-filled blisters appearing about or within the mouth that are caused by a herpes simplex virus and upon rupturing form crusts

called also fever blister

— compare canker sore

Examples of cold sore in a Sentence

Recent Examples on the Web One 2017 study looked at 23 common infections including chickenpox, shingles and cold sores and found genes that seemed to be associated with many of them. oregonlive, "Why do some people die from coronavirus, others hardly get sick? The answer could be your genes," 20 Apr. 2020 Herpes type 1 or oral herpes is a virus that causes painful cold sores on your mouth and lips. Yerin Kim, Seventeen, "How to Get Rid of a Lip Pimple Fast," 16 Jan. 2020 Researchers affilated with the organization estimated that 3.7 billion people under the age of 50 are infected with HSV-1, the type of herpes most people associate with cold sores on the mouth. Kristine Thomason,, "How to Tell if You Have Herpes," 29 Oct. 2019 Cold and flu virus, cold sores, those viruses they're not usually not transferred through food. NBC News, "Are you making these 8 holiday cooking mistakes?," 28 Nov. 2019 Numbing medication caused her reaction In his patient’s case, her reaction was caused by benzocaine, an active ingredient found in over-the-counter toothache and cold sore medicine. Wire Service, The Mercury News, "A woman used a numbing agent to treat a toothache. The next day her blood turned blue," 19 Sep. 2019 Neither Angus or myself have ever had a cold sore in our lives. Michelle Gant, Fox News, "Parents whose newborn babies died from herpes warn about deadly virus," 19 July 2018 There’s some indication that an immune reaction—perhaps from something as seemingly benign as the microbes that cause cold sores or gum disease—could be a spark that launches a series of events that ultimately lead to an Alzheimer’s diagnosis. Karen Weintraub, Scientific American, "Alzheimer’s Meeting: Lifestyle Factors Are the Best—and Only—Bet Now for Reducing Dementia Risk," 18 July 2019 For instance, overexposure to sunlight can bring about immune system suppression, which is why some people with herpes develop cold sores after spending time in the sun. Nina Bahadur, SELF, "Why Does Spending Time in the Sun Make You So Tired?," 8 Sep. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'cold sore.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of cold sore

1870, in the meaning defined above

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Time Traveler for cold sore

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The first known use of cold sore was in 1870

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Cite this Entry

“Cold sore.” Dictionary, Merriam-Webster, Accessed 18 Jan. 2021.

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More Definitions for cold sore

cold sore


English Language Learners Definition of cold sore

: a small sore area around or inside the mouth that is caused by a virus

cold sore


Medical Definition of cold sore

: 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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