Genesis 30:11

בא גד FOR MY HAPPINESS! — Good luck has come, as (Shabbat 67b) “Be lucky, my luck (גד גדי) and tire not”. Similar, also, is (Isaiah 45:11) “That prepare a table for fortune (גד)”. The Midrashic explanation is that he was born with the sign of the covenant upon him. It would then be like (Daniel 4:11) “cut down (גדו) the tree”. I do not know why it (בגד) is written as one word. Another comment on בגד is: why is it read as one word? It may be connected with the root בגד which denotes faithless as though Leah said to Jacob, “You proved faithless to me when you married my handmaid”, like a man who is faithless (בגד) to the wife of his youth).

And Le᾽a said, Fortune comes, and she called his name Gad.

וַתֹּ֥אמֶר לֵאָ֖ה (בגד) [בָּ֣א גָ֑ד] וַתִּקְרָ֥א אֶת־שְׁמ֖וֹ גָּֽד׃