Is there any reason you’re unpopular in your workplace? What kinds of details about past interactions/work dynamic are you possibly leaving out of the post that would be relevant as to why there’s hostility?

Aside from reporting to HR, not much else can be done at this level if it’s the first incident.

If there’s nothing you can do to gain allies amongst your coworkers, it may be prudent to look for a transfer to another location/department with similar duties if there’s no chance to improve your social status in your current situation.

It won’t get you anywhere if you win against this one guy but remain unpopular with people who could come to his defense.