what is the meaning of God

I guess that would be the Bhagavad-Gita itself. The Bhagavad-Gita Eternal Message or Song of God. Again a proper explanation would take more space than this forum has and I'm no Hindi scholar. Still I think that is the essence of it.

Brother

Chapter 4 Text 14

According to the three modes of material nature and the work ascribed to them, the four divisions of human society were created by Me. And, although I am the creator of this system, you should know that I am yet the non-doer, being unchangeable.

one who created this system including you and me is none other than god