The phrase "tap out" can be used in a variety of contexts, such as in sports or competitions, where it means to submit or surrender. Synonyms for this phrase include "give up," "concede," "throw in the towel," "retreat," "capitulate," and "yield." In terms of physical activity, "tap out" can also be used to indicate exhaustion or being unable to continue. Synonyms for this usage include "fatigue," "exhaust," "wear out," "deplete," "drain," and "weaken." Overall, there are many synonyms that can be used instead of "tap out" depending on the context and tone of the situation.