Source : Webster's Revised Unabridged Dictionary (1913)

Test \Test\, Testa \Tes"ta\, n.; pl. E. {Tests}, L. {Test[ae]}.
   [L. testa a piece of burned clay, a broken piece of
   earthenware, a shell. See {Test} a cupel.]
   1. (Zo["o]l.) The external hard or firm covering of many
      invertebrate animals.

   Note: The test of crustaceans and insects is composed largely
         of chitin; in mollusks it is composed chiefly of
         calcium carbonate, and is called the shell.

   2. (Bot.) The outer integument of a seed; the episperm, or
      spermoderm.