To deodorize is to remove or hide bad smells. After cooking fish, you could deodorize your kitchen by burning a cinnamon-scented candle.
Whenever you cover up a stinky odor, you deodorize. Using deodorant under your arms is one way to deodorize, and spraying an air freshener around your house or burning incense are other ways. The word dates from the 19th century, from a combination of de-, "undo" or "do the opposite of," odor, Latin for "a smell," and -ize, a verb-forming suffix.