Boris Karloff was a legendary movie star known for his iconic horror roles. Some of the synonyms for the actor could be the legendary monster man, horror master, or the king of terror. Karloff was the epitome of evil on screen and earned his place in cinematic history as one of the greatest horror actors of all time. Other synonyms that could describe the actor include the horror icon, the Frankenstein's monster, or the master of macabre. Boris Karloff will always be remembered as one of the most influential figures in the horror genre, and his legacy will continue to inspire generations of fans and filmmakers.