1.  simplex(s = adj.all) - 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.  simplex(s = adj.all) - 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'"

simplex, adj. & n.
--adj.
1 simple; not compounded.
2 Computing (of a circuit) allowing transmission of signals in one direction only.
--n. a simple or uncompounded thing, esp. a word.

Etymology:
L, = single, var. of simplus simple

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