Is this correct name translation?

Hello,

Could you tell if I'm translating name "daughter of knowledge/lore" correctly?

Istien or Istiel

Which version (if any) is more correct?

Sorry for the late reply but yes either one will work.

From Eldamo

• -ien An occasional feminine suffix in Sindarin, in one place given as a feminine patronymic (PE17/170) as in the name Lúthien “Daughter of Flowers” (PE17/15, 161). See the entry on the root √YE(L) for a discussion of conceptual vacillations on its connection to “daughter”.

• -iel A widely used feminine suffix in Sindarin (PE17/23, 190). It sometimes more specifically meant “-daughter” in names such as Elrenniel “Arwen; *(lit.) Elrond-daughter” (PE17/56) or Tinúviel “Daughter of Twilight” (S/165), but in other cases it simply meant female as in names like Gilthoniel “Star-kindler [female]” (PE17/23). It was also sometimes reduced to -il or -el. See the entry on the root √YE(L) for a discussion of various conceptual vacillations in its connection to “daughter”.