forewarn > define
verb
- Warn in advance or beforehand; give an early warning.
- usage: "I forewarned him of the trouble that would arise if he showed up at his ex-wife's house"
- synonyms: previse
by WordNet 3.0 © 2006 by Princeton University
(v.t.) To warn beforehand; to give previous warning, admonition, information or notice to; to caution in advance.
by Webster's Revised Unabridged Dictionary