The phrase "pretty pass" is used to describe a difficult or embarrassing situation. There are several synonyms available that can be used to replace this phrase. One of the most common alternatives is "pickle." Another similar phrase is "tight spot." If you are looking for a slightly more formal option, you can use "predicament" or "dilemma" instead. Alternatively, "sticky wicket" and "quandary" are also synonyms that can be used to replace the phrase "pretty pass." All of these options can be used in various contexts, allowing you to choose the one that best suits the tone and theme of your writing or conversation.