sim·​plex | \ ˈsim-ˌpleks How to pronounce simplex (audio) \

Definition of simplex

 (Entry 1 of 2)

1 : simple, single
2 : allowing telecommunication in only one direction a simplex system


plural simplexes

Definition of simplex (Entry 2 of 2)

1 or plural simplices\ ˈsim-​plə-​ˌsēz How to pronounce simplices (audio)\ or simplicia\ sim-​ˈpli-​sh(ē-​)ə How to pronounce simplicia (audio)\ : a simple word
2 : a spatial configuration of n dimensions determined by n + 1 points in a space of dimension equal to or greater than n a triangle together with its interior determined by its three vertices is a two-dimensional simplex in the plane or any space of higher dimension

Examples of simplex in a Sentence

Recent Examples on the Web: Adjective

Medical experts say the procedure is risky because the oral contact puts babies at risk of getting harmful herpes simplex virus type 1 (HSV-1) viruses. Bob Jordan, USA TODAY, "Some babies face herpes risk as N.J. lacks circumcision safety rules," 18 Aug. 2017 Her son Juliano reportedly tested positive for herpes simplex virus type 1 (HSV-1). Caroline Picard, Good Housekeeping, "Mom Shares Terrifying Photos to Warn Parents After Baby Breaks Out in Cold Sores," 31 July 2017

Recent Examples on the Web: Noun

This actually happens often in children who first encounter a herpes simplex or varicella zoster virus somewhere like the playground. Kasandra Brabaw, SELF, "So, You Got Semen in Your Eye. Here's What to Do," 1 Mar. 2019 There are a few exceptions though - herpes simplex virus and varicella can cause a particular type of rash that resembles tiny blisters, are very contagious, and typically require antiviral medication. Gabriela Moraru, M.d., miamiherald, "My child has a rash! What should I do? | Miami Herald," 1 May 2018 Just under half, 48 percent, of people aged 14 to 49 have herpes simplex 1, HSV-1, commonly known as the cold sore virus. Maggie Fox /, NBC News, "Half of Americans have cold sore virus; 12 percent genital herpes," 7 Feb. 2018 Herpes simplex virus type 1, or HSV-1, usually causes cold sores in the mouth area, while HSV-2 leads to genital sores. Jenelle Marie Pierce, Allure, "The Oral Sex Risk You’re Not Thinking About," 23 Aug. 2017 For starters, there are two different kinds: herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2). Jenelle Marie Pierce, SELF, "First Lesson of Herpes Transmission: There Is Pretty Much No Way to Know Who Gave You Herpes," 3 Aug. 2017 The current owners, Othon and Kathy Prounis, bought the simplex, No. Vivian Marino, New York Times, "Exclusive | 1150 Fifth Avenue," 30 Sep. 2016 On top of that, 417 million people have herpes simplex virus type 2 (HSV-2), which causes genital herpes. Elizabeth Narins, Cosmopolitan, "2 Out of 3 People Have Herpes," 30 Oct. 2015 And yes! The list of diseases transmitted through oral sex includes chlamydia, syphilis, gonorrhea, herpes simplex virus and HPV. Jan Hoffman, New York Times, "The Persistent Myth About Oral Sex," 7 Apr. 2016

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'simplex.' 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 simplex


1594, in the meaning defined at sense 1


1892, in the meaning defined at sense 1

History and Etymology for simplex


Latin simplic-, simplex — more at simple

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The first known use of simplex was in 1594

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Medical Definition of simplex

More from Merriam-Webster on simplex

Rhyming Dictionary: Words that rhyme with simplex Encyclopedia article about simplex

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