Definition - What does Guruji mean?
Guruji is a word made up of the Sanskrit word, guru, meaning “teacher,” “guide” or “master,” and the suffix -ji, which is commonly used in many South Asian language as a gender-neutral honorific. As such, the whole term guruji is a very respectful and affectionate term for one’s guru or spiritual teacher. It may be used especially used in Hinduism and Tibetan Buddhism.
In some cases, specific spiritual teachers may be known to their students as "guruji" in place of their actual name.
Yogapedia explains Guruji
The role of a guruji is traditionally considered to be more than simply a teacher. A guru is one who takes their students towards the light, dispelling darkness. They are a reverential figure, as well as a role model, mentor, counsellor and source of inspiration. To address a guru with the term guruji will express the students' deepest admiration for their guru.
Some say that because -ji is an honorofic suffix, it should always be an individual student’s choice as to whether to use it or not. As such no spiritual teacher should add the -ji to their own name, or it loses the value of when it chosen to be used by a student or disciple.