c.1585, from L.L. gnosticus,
from Late Gk. gnostikos,
noun use of adj. gnostikos
"knowing, able to discern," from gnostos
"knowable," from gignoskein
"to learn, to come to know" (see know
). Applied to various early Christian sects that claimed direct personal knowledge beyond the Gospel or the Church hierarchy. The adj. meaning "relating to knowledge" (with lower-case g-
) is from 1656.