"Blend of John and -ita"
The name Johnita is commonly a female name from the "English" origin.
Johnita is a feminine name built from John plus the diminutive ending -ita, the same ending that forms Spanish diminutives such as Juanita and Rosita. In English use it reads as a pet form of John rather than as a name with a separate meaning of its own. It has been recorded in United States birth records since 1924.
The pronunciation of Johnita is joh-NEE-tuh.