See more synonyms for simplex on
  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 sim·plex·es, sim·pli·ces [sim-pluh-sees] /ˈsɪm pləˌsis/.
  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.

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 (see homo-), English same) + -plex -plex Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for simplex

Historical Examples of simplex

British Dictionary definitions for simplex


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

Word Origin for simplex

C16: from Latin: simple, literally: one-fold, from sim- one + plex, from plicāre to fold; 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

Word Origin and History for simplex

"characterized by a single part," 1590s, from Latin simplex "single, simple, plain, unmixed, uncompounded," literally "onefold," from PIE root *sem- "one, together" (cf. Latin semper "always," literally "once for all;" Sanskrit sam "together;" see same) + *plac- "-fold," from PIE *plek- "to plait" (see ply (v.1.)). The noun is attested from 1892, "simple uncompounded word."

Online Etymology Dictionary, © 2010 Douglas Harper