as a girls' name has its root in Hebrew, and the meaning of the name Lyse is "God is my oath". Lyse is an alternate spelling of Elizabeth (Hebrew).
Where is Lyse from?
Lyse was born in the village of Ala Gannha in the Peaks of Gyr Abania, where she grew up with her father Curtis and older sister Yda.
Did we ever see the real Yda?
↑ 3.03.13.23.3 With the Echo visions occurring in 1562 and Yda's death occurring in 1571, it can be inferred that the Yda seen in the Echo visions of the Gridania storyline during the original release was in fact the real Yda, as Lyse did not begin adopting her sister's identity until after her death.