Meaning and name origin
Robertha \r(o)-ber-tha, rob(e)-rtha\ as a girl's name is of Old English and Old German origin, and the meaning of Robertha is "bright fame". Robertha is a variant of Roberta (Old English, Old German): feminine of Robert. Not extensively used as a given name for baby girls.
Robertha is not a popular first name for females and an equally uncommon surname or last name for all people (Source: 2000 U.S. Population Census).
Displayed below is a comparison of the popularity of the girl name Robertha and its source form. The only popular variation form ranked in the Top 1000/100 is Roberta. (Source: 2014 Birth Name Statistics).