Mahaji

Mahaji may not be a Sanskrit term, although Mataji (revered mother) is. Have you come across the expression? I think it is used in Thailand. Mahaji may be a title for Shiva.

In India at least, "Mahaji" is not in popular use. Shiva is called Mahadev - the Great Lord. Maha means "great", and "ji" is a suffix of honor. It may be in use in other countries.