adversary (n.)
- alien
- antagonist
- anti
- assailant
- combatant
- competitor
- con
- contradictory
- contrary
- counter
- cross
- devil
- enemy
- foe
- foeman
- hostile
- negative
- opponent
- opposite
- refractory
- rival
My desire is . . . that mine adversary had written a book.
Be sober, be vigilant; because your adversary, the Devil, as a roaring lion, walketh about, seeking whom he may devour.