The name Giana is of Italian origin and means "God Is Gracious." The origin is the culture in which the name originated, or in the case of a word--the language in which it most appears.
Italian feminine form of John
Giana is on 3,527 members' favorite name lists Giana is currently not ranked on the Baby Names popularity charts Giana is currently #80 in U.S. births.
Giana 
