What does forewarning mean?
A forewarning is an advance notice of something yet to come — most often a danger, hardship, or piece of unwelcome news. To give someone forewarning is to alert them before the fact, allowing time to prepare, adapt, or take cover; conversely, an event that arrives 'without forewarning' catches people entirely unprepared. The word functions as both an everyday noun ('we had ample forewarning of the strike') and a technical one, appearing in psychology and communication research to describe advance notice of an upcoming persuasive message. Its connotations are largely practical and protective: forewarning implies foresight, prudence, and a fair chance to respond. The old proverb 'forewarned is forearmed' captures this logic neatly, suggesting that knowledge of a threat in advance is itself a kind of defense. In tone it sits between the casual 'heads-up' and the literary 'portent,' making it useful wherever clarity and a touch of formality are wanted.
Advance notice or caution concerning a future event, especially one involving danger, loss, or difficulty.
"Thanks to the meteorologist's forewarning, coastal towns had sandbags in place days before the flood."
Often used with negation ('without forewarning') to emphasize that something came as a complete surprise.
A presentiment or intuitive sense that something is about to happen (less common sense).
"A vague forewarning made her check the stove twice before leaving the house."
This sense overlaps with 'premonition' but is less common and tends toward the informal or figurative.
The plural is regular and used when multiple separate notices are being discussed, though the singular is far more common in practice.
"Despite repeated forewarnings from regulators, the firm continued its risky practices."
The phrase 'forewarned is forearmed' traces back over four centuries — and 'forewarning' still carries that same promise of a fighting chance before trouble arrives.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of forewarning
Forewarning derives from the verb 'forewarn,' formed in Middle English by prefixing 'fore-' (before) to the Old English verb 'warnian,' meaning to caution or make aware. The base verb 'warn' comes from the Germanic root *warōn/*wara-, which also gave rise to words such as 'ware' and 'beware,' all concerned with vigilance against danger. As a distinct noun, 'forewarning' developed naturally from compounds like 'forewarned,' long cemented in English by the proverb 'forewarned is forearmed,' attested by the sixteenth century.
Related word forms
How forewarning is actually used
Forewarning is typically a formal or neutral term; in casual speech people more often say 'a heads-up' or 'advance notice.' It carries a practical, protective connotation and appears frequently in contexts involving risk, weather, security, and research on persuasion (where 'forewarning' describes advance notice of a persuasive attempt).
Easily confused with forewarning
Foreshadowing is a literary device in which clues hint at future events within a story, whereas a forewarning is an actual notice or caution given to someone in real life.