Dr J is a common abbreviation for the famous retired basketball player Julius Erving. However, when it comes to synonyms for "Dr J," there are several options depending on the context. For example, if we are talking about a medical doctor with the initials J, we could use "Dr J" as a shorthand. Alternatively, if we are looking for other names/nicknames for Julius Erving, we could use "The Doctor," "Dr. Dunk," or simply "Julius." In a broader sense, if we want to find synonyms for a doctor who is a specialist in a particular area, we might use terms like "expert," "specialist," or "practitioner" to describe them.