The phrase "x out" can have a variety of meanings in the English language, and there are many synonyms for each meaning. If "x out" refers to removing something or canceling a task, synonyms include delete, eliminate, scrub, and cross off. In terms of closing or shutting down, synonyms for "x out" could include exit, close, shut down, and terminate. Finally, if "x out" means to blackout or forget something, synonyms may include blank out, forget, or fail to remember. Using synonyms for different meanings of "x out" can help to clarify and add nuance to your language.