enemy

(noun) an opposing military force. Example: "The enemy attacked at dawn."

(noun) an armed adversary (especially a member of an opposing military force). Synonyms: foe, foeman, opposition. Example: "A soldier must be prepared to kill his enemies."

(noun) any hostile group of people. Example: "He viewed lawyers as the real enemy."

(noun) a personal enemy. Synonyms: foe. Example: "They had been political foes for years."