adversary

These actions include revoking security clearances, publicly calling for firings, and praising legal actions against former political adversaries, such as the indictment of former FBI Director James Comey.

He has targeted law firms he sees as adversaries, pulling government security clearances and contracts.

This, for so many Labour folk, is not merely the traditional political tussle with the party's oldest adversary, the Conservatives.

His adversaries think he’ll crumple like yesterday’s broadsheet when they turn him away, and are perturbed to realize he’s more like the human equivalent of tissue hanging onto the heel of a shoe.

A legal complaint, the judge said, is not "a protected platform to rage against an adversary".