Oh-oh is an expression used to indicate that something has gone wrong or something bad is about to happen. It is a colloquial term used to express concern, worry, or sudden realization. Synonyms for oh-oh include uh-oh, oops, yikes, whoops, darn, shoot, gosh, and blimey. These expressions can be used in various situations, such as when you realize you have made a mistake, when something unexpected happens, or when you feel concerned about something. Oh-oh and its synonyms are part of the typical informal language that people use in their daily lives, and they can add humor or emphasis to a conversation.