opponent
US /əˈpoʊ.nənt/
UK /əˈpoʊ.nənt/

1.
oponente, adversario
someone who competes against or fights another in a contest, game, or argument
:
•
He defeated his opponent in the final round.
Derrotó a su oponente en la ronda final.
•
The debaters presented strong arguments against their opponents.
Los debatientes presentaron fuertes argumentos contra sus oponentes.
2.
oponente, detractor
a person or group who is against something, such as a policy, idea, or action
:
•
The new policy faced strong resistance from its opponents.
La nueva política enfrentó una fuerte resistencia de sus oponentes.
•
She became a vocal opponent of the proposed development.
Se convirtió en una opositora vocal del desarrollo propuesto.