Simplex
WordNet
adjective
(1) Allowing communication in only one direction at a time, or in telegraphy allowing only one message over a line at a time
"Simplex system"
(2) Having only one part or element
"A simplex word has no affixes and is not part of a compound--like `boy' compared with `boyish' or `house' compared with `houseboat'"
WiktionaryText
Adjective
Noun
- An analogue in any dimension of the triangle or tetrahedron: the convex hull of n+1 points in n-dimensional space.
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Adjective
; third declension