Gnos"tic (?), a. 1. Knowing; wise; shrewd. [Old Slang]

I said you were a gnostic fellow.

2. (Eccl. Hist.) Of or pertaining to Gnosticism or its adherents; as, the Gnostic heresy.

Gnos"tic, n. [L. gnosticus, Gr. &?; good at knowing, sagacious; as a n., man that claims to have a deeper wisdom, fr. gignw`skein to know: cf. F. gnostique. See Know.] (Eccl. Hist.) One of the so-called philosophers in the first ages of Christianity, who claimed a true philosophical interpretation of the Christian religion. Their system combined Oriental theology and Greek philosophy with the doctrines of Christianity. They held that all natures, intelligible, intellectual, and material, are derived from the Deity by successive emanations, which they called Eons.

• Of, or relating to, intellectual or spiritual knowledge
  
• Of, or relating to Gnosticism
  
• A believer in Gnosticism