Diminutive of Elizabeth, from Hebrew Elisheva meaning 'God is my oath.'
Betsy began its life as an 18th-century English pet form of Elizabeth, that towering biblical name derived from the Hebrew Elisheba, meaning "my God is an oath" or "my God is abundance." The diminutive chain that produced Betsy is a characteristically English one — Elizabeth begat Bess, Bess begat Bessy, Bessy softened to Betsy — each step carrying the name further from the throne rooms and saints' days of its origin toward something warmer, more domesticated, more affectionately human.
By the American colonial period, Betsy was widely in use as a standalone name among ordinary families. No single person anchors Betsy to American mythology more firmly than Betsy Ross, the Philadelphia seamstress and upholsterer credited — through a story likely embellished by the 19th century — with sewing the first American flag at George Washington's request. Whether historically precise or not, the tale lodged the name permanently in the national imagination, giving Betsy a patriotic, industrious, capable character.
Through the 19th and early 20th centuries the name thrived; Betsy Trotwood, the eccentric aunt in Dickens's David Copperfield, gave it a literary wit. By the late 20th century Betsy had retreated from mainstream use, but it has returned in recent years as part of a broader enthusiasm for sweet, uncluttered vintage names that feel both retro and quietly chic.