Having renounced or rejected by solemn oath; perjured or broken in oath; apostate.
From the past participle of 'forswear.' The adjective form means someone who has completed the action of forswearing and exists in that renounced state.
A 'forsworn' person in Shakespeare is typically either religiously apostate or politically turned—the word carries shame because you've broken a sacred oath, not just changed your mind.
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