Forwarn

Part of speech: verb

Definitions

1. To alert a person beforehand about a danger, problem or unpleasant event that is about to happen
2. To give someone notice ahead of time so they can prepare for something harmful or unwelcome
3. Advising a person in advance of a coming threat, difficulty or unwelcome development so they can respond

Etymology: The most surprising thing about "forwarn" is that its ancestor meant almost the opposite of warning. In Old English, "forwærnan" meant to hinder, prohibit, prevent or refuse, and it was built from a prefix meaning "for-" (in the sense of "away" or "against") attached to a root that meant "to care" or "to worry". Refusing and forbidding were close to guarding against something, and that protective sense eventually turned into the modern idea of giving someone notice of trouble ahead. The word arrived in Middle English as "forwernen", which kept the older senses of denying, withholding and opposing. The shift toward advance warning happened gradually, so the modern sense is a later development that grew out of the older idea of keeping harm away. The root traces back further to a Proto-Indo-European verb meaning "to close, cover, protect, defend", which explains why an earlier sense of keeping something off or out sits behind the modern one.

Synonyms: forewarn, warn, alert