The antonyms for the word "depressurize" are "pressurize," "inflate," and "pump up." These words describe the opposite of depressurizing, which means to increase the pressure inside a container or system. Pressurizing is often necessary for things like tires, air conditioning units, or even aerospace equipment. Inflating is commonly used to describe filling a balloon, ball, or tire with air. Pumping up refers to adding air or pressure to a specific area. Using these antonyms, you can accurately convey the opposite meaning of depressurizing in your writing or speech.