Archfoe

Part of speech: noun

Definitions

1. A bitter or implacable enemy regarded as the most dangerous or important adversary one faces
2. The chief antagonist or most formidable foe in a conflict or rivalry
3. One's greatest rival or opponent, especially in a prolonged struggle or contest

Etymology: "Archfoe" is a plain compound: the prefix "arch-", meaning chief or principal, attached to "foe." The prefix comes from Greek "arkhos," a leader or ruler, and it appears in older English words such as "archbishop" and "archduke," where it marks the top rank among its kind. "Foe" is a much older English word, descending from Old English "fāh" and related to words for hostility and enmity in other Germanic languages. Put together, the compound names the principal enemy: not just any opponent, but the one who stands above the rest in a rivalry or conflict. Its meaning follows directly from the parts, with no shift in sense along the way. The prefix has been productive in English for centuries, which is why a writer can attach it to almost any noun of enmity or rivalry and be understood at once.

Synonyms: archenemy, nemesis, enemy

Antonyms: ally, friend