When something is off, it can mean that it is not functioning properly or that it is not quite right. There are many different ways to express this same sentiment using synonyms. For example, you could say that something is amiss, not up to par, or askew. You could also describe the situation as being askance, wrong, or astray. Other possible synonyms for is off include erroneous, flawed, defective, faulty, or skewed. Each of these words can be used to convey a slightly different shade of meaning, so it's important to choose the right synonym based on the context and the specific message you want to convey.