Whether or no is an expression used to introduce a choice between two possibilities. It is often used to indicate uncertainty or doubt about a situation. If you need to use a synonym for whether or no to make your writing more varied or concise, there are several options available. One possible alternative is regardless of whether, which implies that the outcome of the choice is not important. Another option is whether or not, which is a slightly more formal version of whether or no. Alternatively, you could use phrases like if or not, if at all, or even if, depending on the context.