Jī (Hindi: जी, Urdu: جی,) is an honorific used as a suffix in Hindi-Urdu and many other languages of the Indian subcontinent. Its usage is similar, but not identical, to another subcontinental honorific, sāhab. Similar to the Japanese honorific -san, ji is gender-neutral and can be used for as a term of respect for inanimate objects as well. Ji can mean respect: With names, e.g. Abbas-ji, Gandhiji, Sant Ji or Mullah Ji With inanimate objects of respect, e.g. Gangaji or Kailashji For groups to whom respect is extended, e.g. Khalsa Ji To denote respect in any relation, e.g. Baba-ji (respected father), Uncle-ji, Behen-ji (respected sister), Devi-ji (respected madam) In conversation, e.g. "Ji Nahi" (No, said with respect) In polite conversation, e.g. "Navraj Ji" (Mr. Navraj, similar to how it would be said in Japanese, Navraj-san) As a shorthand for yes or to denote respectful attention, "Ji" To reassure that a request has been understood and will be complied with, "Ji Ji" To respectfully ask for clarification, "Ji?" (with a questioning tone)

Ji is added behind the name as a mark of respect

It literally means "King" in English with the "ji" adding a sense of respect. But this word could be used to call anyone in a playful and friendly manner, i guess.