This spelling originated from Goa on the West Coast of India.
[1] It is also an Arabic and Hebrew surname and masculine given name derived from Mount Sinai.
[2] In the United States, the 2010 Census found 367 people with the surname Sinai, making it the 55,841st-most-common name in the country.
In both censuses, about eight-tenths of the bearers of this surname identified as white, one-tenth as Hispanic, and three percent as Asian.
[3] The Sinai families in India belong to the Brahmin caste.