Uh-oh is an expression used to indicate surprise, concern, or disappointment, often in response to an unexpected situation. There are several synonyms for this phrase, each with its own nuance and tone. Some of the common alternatives include "oops," "uh-uh," "oh no," "aw man," "shoot," "darn" and "blast." Depending on the situation, one might choose to use a particular synonym to convey a specific emotion or degree of seriousness. For example, "oops" is a lighthearted term that can indicate a minor mistake, while "oh no" suggests more significant trouble or danger.