{ Test (?), Testa (?), } n.; pl. E. Tests (#), L. Testæ (#). [L. testa a piece of burned clay, a broken piece of earthenware, a shell. See Test a cupel.] 1. (Zoöl.) The external hard or firm covering of many invertebrate animals.
[1913 Webster]

&hand_; 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.
[1913 Webster]

2. (Bot.) The outer integument of a seed; the episperm, or spermoderm.
[1913 Webster]