The Collaborative International Dictionary of English v.0.48:

Prescious \Pre"scious\ (pr[=e]"sh[u^]s), a. [L. praescius; prae
   before + scius knowing, fr. scire to know.]
   Foreknowing; having foreknowledge; as, prescious of ills.
   [R.] --Dryden.
   [1913 Webster]