Final answer:
The words nemesis and enemy have similar meanings and can both refer to someone or something that is regarded as a source of harm or downfall.
Step-by-step explanation:
The words nemesis and enemy are almost synonyms, not antonyms. They have similar meanings and can both refer to someone or something that is regarded as a source of harm or downfall. For example, if someone is your nemesis, they are your opponent or rival, whereas an enemy is someone who is actively opposed or hostile to you.
Learn more about Synonyms and antonyms