Technically, no. Titles for teachers vary quite a bit depending on position, degree, and experience. Professors almost always hold a terminal degree (doctorate/Ph.D. or master of fine arts/ MFA for creative disciplines), but even then they may be considered an instructor. There are different levels of professors as well. But when it comes to gift ideas, the best thing to keep in mind is that they still can make use of the same gifts, no matter the prestige of their title!