enemy, foe, foeman, opposition (noun)

an armed adversary (especially a member of an opposing military force)

"a soldier must be prepared to kill his enemies"

foe, enemy (noun)

a personal enemy

"they had been political foes for years"

Foe

Foe is a 1986 novel by South African-born Nobel laureate J. M. Coetzee. Woven around the existing plot of Robinson Crusoe, Foe is written from the perspective of Susan Barton, a castaway who landed on the same island inhabited by "Cruso" and Friday as their adventures were already underway. Like Robinson Crusoe, it is a frame story, unfolded as Barton's narrative while in England attempting to convince the writer Daniel Foe to help transform her tale into popular fiction. Focused primarily on themes of language and power, the novel was the subject of criticism in South Africa, where it was regarded as politically irrelevant on its release. Coetzee revisited the composition of Robinson Crusoe in 2003 in his Nobel Prize acceptance speech.