Antonyms, or opposites, for the word "unthreatened" include threatened, endangered, vulnerable, unsafe, and insecure. These terms describe situations or individuals that are in danger or at risk of harm. For example, a threatened species is one that is at risk of becoming extinct due to environmental factors, while an insecure person may lack self-confidence and feel uncertain about their safety. It's important to understand antonyms as they help to provide a full understanding of a word's meaning and nuance. By understanding both the positive and negative connotations of a word, we can communicate more effectively and accurately in our writing and speech.