According to a legend, the name Shenandoah means "Beautiful Daughter of the Stars", and in some versions, simply "Daughter of the Stars." This story, passed down through Native American tradition, tells of a time when a vast, still lake covered the Shenandoah Valley. Its waters were so calm and clear that the night sky was reflected perfectly on its surface, creating the illusion that the stars had touched the earth. People believed the stars watched over the valley, and from their shimmering reflection came a radiant presence, a daughter born of the heavens above and the waters below. Eventually, the great lake flowed out through a natural opening in the mountains, forming the Shenandoah River. Though the lake disappeared, the river remained, carrying with it the name and the legend of the Beautiful Daughter of the Stars.

This version or similar shared by these sources:

• What’s in a Name? Let’s Talk Shenandoah

• ​Shenandoah

• ​Shenandoah and Its Native American Roots

​The most authoritative version may be from ​Julia Davis, "The Shenandoah", in 1945.  Davis when describing the evolution of the Shenandoah name says, "The most romantic one, the one popularly accepted by the Valley people themselves, is “Daughter of the Stars.” This meaning has been much beloved, and incorporated into the writing which every generation of inhabitants feels inspired to produce, but the basis for it has remained concealed from the present researcher"  She goes on to say, "But these discussions matter little. As Daughter of the Stars the river has been enshrined in the hearts of Valley dwellers, and Daughter of the Stars it will remain to them."

​I guess that is true for this valley dweller too as the names “Beautiful Daughter of the Stars,” and "Daughter of the Stars" resonated with me immediately and I think of this name often when hiking through her hills.  

PS - the Wikipedia citation for the Davis quote above says it is on pages 20 - 21, but it is on page 16, at least inthe Project Muse version I read.