antagonistic
adj.showing strong dislike or opposition toward someone or something. You use this to describe a person or a situation where people are acting like enemies.
adj.showing or feeling active opposition or hostility toward someone or something. Often used to describe interpersonal relationships or political stances characterized by conflict.
“The two neighbors have an antagonistic relationship.”
“The debate turned sour when the candidates began using antagonistic language instead of discussing the actual policy.”
“While some competition can drive innovation, an overly antagonistic corporate culture often leads to high employee turnover and a breakdown in internal communication.”
Often followed by the preposition 'to' or 'toward'.
“We learn about Capone’s short but lively trip to Hollywood and his initially antagonistic, but ultimately positive reception to the loose biopic made about him in 1932, Scarface.”
“When Kristian is home for Christmas, he’s antagonistic towards his family, too.”
From antagonist + -ic.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.