primitive vs simplex

primitive

noun
  • An original or primary word; a word not derived from another, as opposed to derivative. 

  • A simple-minded person. 

  • A data type that is built into the programming language, as opposed to more complex structures. 

  • A basic geometric shape from which more complex shapes can be constructed. 

  • Any of the simplest elements (instructions, statements, etc.) available in a programming language. 

  • A member of a primitive society. 

  • A function whose derivative is a given function; an antiderivative. 

adj
  • Of or pertaining to or harking back to a former time; old-fashioned; characterized by simplicity. 

  • Occurring in or characteristic of an early stage of development or evolution. 

  • Crude, obsolete. 

  • Not derived from another of the same type 

  • Original; primary; radical; not derived. 

  • Of or pertaining to the beginning or origin, or to early times; original; primordial; primeval; first. 

simplex

noun
  • A monomorphemic word, one without affixes. 

  • An analogue in a space of arbitrary dimensionality of the triangle or tetrahedron; the convex hull of n+1 linearly independent points in n-dimensional space; in other words, the triangle, tetrahedron etc., generalized to an arbitrary number of dimensions. 

adj
  • Single, simple; not complex. 

  • Unidirectional. 

How often have the words primitive and simplex occurred in a corpus of books? (source: Google Ngram Viewer )