Other forms: offendedly
Someone who's offended is annoyed, hurt, or disgusted. If one presidential candidate comments snidely on the hairstyle of another, the offended candidate may retaliate.
If your feelings are hurt by your brother's comment that he "could take or leave" the chocolate chip cookies you baked for him, you're offended. And your grandmother's offended expression may be the result of the dreadful movie you're watching. Offended comes from the verb offend, specifically its secondary meaning "to wound the feelings." The Latin root is offendere, "to hit, stumble, provoke, or displease."