The word "faulty" refers to something that has a defect or a flaw. There are several synonyms that can be used instead of "faulty" such as defective, flawed, faulty, impaired, imperfect, and substandard. Each of these synonyms refers to something that is not working as it should or does not meet the expected standard. Defective implies that the item is incomplete or has a missing component, flawed suggests it has an inherent defect that will cause problems, impaired refers to something that is damaged, imperfect indicates that it is not the best quality, and substandard implies that it is below average. Each synonym offers an alternative way of expressing that something is not working effectively or is unsatisfactory.