An Etymological Dictionary of Astronomy and Astrophysics

Situated within or farther within; interior.

Etymology (EN): From O.E. inra, comparative of inne (adv.) “inside;” → in-.

Etymology (PE): Daruni, adj. of darun “in, into; within” (Mid.Pers. andarôn
“inside,” from andar, → inter-, + rôn “side, direction;” Av. ravan- “(course of a) river”).