The antonyms for "x outing" can vary depending on the context of the word. If "x outing" refers to a social event or activity, its antonyms could be "staying in," "quiet night," or "solo time." If it refers to disclosing someone's confidential information or secret, its antonyms could be "keeping silent," "keeping quiet," or "respecting privacy." Another antonym could be "canceling," which implies that plans have been terminated or not initiated at all. Overall, the antonyms for "x outing" reflect the opposite action or behavior associated with the word, whether it's socialization or secrecy.