Variant spelling of Dorothy, from Greek meaning 'gift of God.'
Dorthy is an American vernacular spelling of Dorothy, and both ultimately descend from the Greek *Dorothea*, itself a reversal of the earlier *Theodora* — the same two elements (*doron*, gift, and *theos*, God) simply reordered to mean 'gift of God.' The name entered the English-speaking world through early Christian martyrology: Saint Dorothea of Caesarea, a fourth-century martyr, was said to have been mocked by a skeptic as she walked to her execution, and to have miraculously sent him a basket of heavenly roses and apples in February — a story that made her the patron of florists and gardeners across medieval Europe. By the early twentieth century Dorothy had become one of the most popular girls' names in the English-speaking world, and the spelling Dorthy appeared as a common informal variant in American birth registrations, particularly in the rural South and Midwest.
The era's most iconic Dorothy, of course, is the Kansas farm girl in L. Frank Baum's *The Wonderful Wizard of Oz* (1900), immortalized on screen by Judy Garland in 1939. That cultural touchstone fixed the name in the American imagination as warm, plucky, and fundamentally good-hearted — a girl who, when faced with the impossible, simply keeps moving forward.
The Dorthy spelling carries an additional layer of authenticity: it is the name as a grandmother or great-grandmother might have written it in her own hand, a documentary echo of early twentieth-century American life. It has the texture of a family name passed down before record-keeping was standardized, and for many families that is exactly what it is.