<p><strong>Adjective</strong></p><ul><li>simple; consisting of or characterized by a single element</li><li>pertaining to or noting a telecommunications system permitting communication in only one direction at a time</li></ul><p><strong>Noun</strong></p><ul><li>plural: simplex, simplices</li><li>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</li><li>an apartment having all the rooms on one floor</li></ul>