Indistinguishable is a descriptive word that is used to mean that two or more things are difficult to differentiate or tell apart. Synonyms for indistinguishable include identical, alike, similar, same, uniform, congruent, and corresponding. Other similar terms include interchangeable, equal, equivalent, comparable, and homogeneous. These words are often used to describe things that are so similar that they appear almost identical. For instance, two things can be similar, but not necessarily indistinguishable. Similarly, two things can be identical without being the same. The use of synonyms helps to add variety to written or spoken language while providing clarity and precision in communication.