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Synonyms

simplex

American  
[sim-pleks] / ˈsɪm plɛks /

adjective

  1. simple; consisting of or characterized by a single element.

  2. pertaining to or noting a telecommunications system permitting communication in only one direction at a time.


noun

plural

simplexes, simplices
  1. Mathematics. a basic geometric element in a Euclidean space, being a line segment in one dimension, a triangle in two dimensions, a tetrahedron in three dimensions, and so on: used in topology and linear programming.

  2. an apartment having all the rooms on one floor.

simplex British  
/ ˈsɪmplɛks /

adjective

  1. permitting the transmission of signals in only one direction in a radio circuit, etc Compare duplex

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

noun

  1. linguistics a simple not a compound word

  2. geometry the most elementary geometric figure in Euclidean space of a given dimension; a line segment in one-dimensional space or a triangle in two-dimensional space

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of simplex

1585–95; < Latin: having a single layer, literally, one-fold, equivalent to sim-, base meaning “one” (akin to similis similar, Greek hén (neuter) one, homós same ( homo- ), English same ) + -plex -plex

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

In Fayetteville, North Carolina, in 2020, as in other military towns across the U.S., rates of sexually transmitted infections like syphilis, herpes simplex and HIV are among the highest in the country.

From Salon • Jul. 20, 2025

Important conclusions from the study include the need to further investigate whether already known drugs against the herpes simplex virus can reduce the risk of dementia and the possibility of developing new vaccines.

From Science Daily • Feb. 14, 2024

Deaths caused by HSV-1 - herpes simplex 1 - are almost unheard of in healthy people.

From BBC • Jul. 26, 2023

The treatment, called Vyjuvek, uses an inactivated herpes simplex virus to deliver working copies of that gene.

From Seattle Times • Jul. 24, 2023

A non-singular cubic is simplex, consisting of one odd circuit, or it is complex, consisting of one odd circuit and one even circuit.

From Encyclopaedia Britannica, 11th Edition, Volume 7, Slice 8 "Cube" to "Daguerre, Louis" by Various