Use professor only to refer to faculty members who have earned that academic rank. Any variations of professor, such as associate professor or professor emeritus, should be used. The preferred use is to put the title after someone’s name. Ex: Jane Doe, an assistant professor at the Missouri School of Journalism.
Non-tenured track faculty members are typically identified as “teaching” or “research” professors. Adjunct faculty are instructors employed by the university who are neither tenured nor in tenure-track positions.