late 14c., "small vessel used in assaying precious metals," from Old French test, from Latin testum "earthen pot," related to testa "piece of burned clay, earthen pot, shell" (cf. Latin testudo "tortoise") and texere "to weave" (cf. Lithuanian tistas "vessel made of willow twigs;" see texture (n.)).
Sense of "trial or examination to determine the correctness of something" is recorded from 1590s. The connecting notion is "ascertaining the quality of a metal by melting it in a pot." Test Act was the name given to various laws in English history meant to exclude Catholics and Nonconformists from office, especially that of 1673, repealed 1828. Test drive (v.) is first recorded 1954.