simplex

containing, using, or designed for a single element or component

allowing transmission of signals or communication in only one direction at a time

an apartment with all rooms on one floor

a word in its base form, without any inflections, prefixes, or suffixes, and not formed by putting two distinct words together.

a geometrical element in a Euclidean space that exhibits the minimum number of dimensions of the space, e.g. a line in one-dimensional space or a triangle in two-dimensional space