Bertha \b(e)-rtha, ber-tha\ as a girl's name is pronounced BER-thah. It is of Old German origin, and the meaning of Bertha is "bright, famous". Latin version of a Continental German name. The name of two French saints (eighth and ninth century). Also related to the name of a Teutonic goddess. The name probably existed in England before the Conquest, and was reinforced by Norman use, but fell out of use in the 15th century. It was reintroduced into the English-speaking world by Germany in the 19th century. A German cannon used in World War I was nicknamed "Big Bertha" after Bertha Krupp, daughter of the family that manufactured the weapon. Berta is a Spanish and Italian form; Berthe and Bertine are French.
Bertha has 21 variant forms: Berrta, Berrte, Berrti, Berrtina, Berrty, Berta, Berte, Berthe, Berti, Bertie, Bertina, Bertine, Bertita, Bertuska, Berty, Bird, Birdie, Birdy, Birta, Birtha and Laberta.
For more information, see also related names Bartha and Bertrice.