What adjective describes someone who is hostile and aggressive?

The adjective "belligerent" effectively captures the essence of being hostile and aggressive. It is derived from the term that originally described nations or individuals engaged in war or conflict. Therefore, it implies a readiness to fight or argue, which aligns closely with the characteristics of hostility and aggressiveness. In contexts where someone's behavior is confrontational or combative, describing them as belligerent accurately conveys those aggressive tendencies.

Other options do not fit the context of hostility. "Laudable" denotes something deserving of praise, "substantive" refers to something significant or meaningful, and "conducive" indicates something that is helpful or favorable. None of these terms convey the notion of aggression or hostility, reinforcing why "belligerent" is the appropriate term for describing someone with a hostile and aggressive demeanor.