A person who warns or alerts others in advance about something that might happen.
From 'forewarn' + '-er' (agent suffix meaning 'one who'). The suffix '-er' is added to verbs to create nouns for people who perform that action. This word is relatively rare in modern English.
Historically, forewarners were often prophets or soothsayers—people the community believed could see into the future and warn them of dangers. It's a word that connects to our ancient fascination with prediction.
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