The only named female dwarf in Tolkien’s works is Dís. She is the daughter of Thráin II, sister of Thorin Oakenshield, and mother of Fíli and Kíli.
Dís belongs to the line of Durin and lived in Erebor before Smaug drove the Dwarves from the Lonely Mountain. Her sons later fought in the Battle of Five Armies, where both were killed defending Thorin.
Tolkien explains that Dwarven women were fewer in number than men—no more than one-third of the population—and were rarely seen outside their own settlements. This helps explain why so few are mentioned by name.
Dís is sometimes confused with Gimli’s mother or with an unnamed female relative of another Dwarf, but Tolkien gives no names for them. Her name is significant precisely because she is the sole explicitly named female Dwarf in the published legendarium.