What does ji means in Hindi?

Answer 1

Depends upon context.

If placed at the end of a person's name (e.g. referring to someone named Prakash as Prakashji), it is a sign of respect or admiration. The class system of India (Caste System) has conferred a strong sense of social hierarchy. One would add "ji" to those occupying a higher social stratum. It may also be used in a familiar way to show genuine, respectful affection.

A common example is to call one's spiritual guide "Swamiji". The word Swami has the meaning of Teacher. To call one's spiritual teacher Swamiji indicates the devotion and respect that the student has.

Answer 2

"Ji" is a term of respect used in Hindi to address someone with politeness and formality. It is often added after a person's name or title when speaking to them to show respect.