What does Hilda mean?
Built on the Germanic element 'hild' meaning 'battle'. It began as a short form of longer names such as Hildegard and Brunhild before becoming an independent name.
What does Zelda mean?
Commonly a short form of Griselda, from Germanic 'gris' (grey) and 'hild' (battle). A separate Yiddish name Zelda meaning roughly 'blessed/happy' also exists, so the battle sense specifically traces to the Griselda line.