Etymograph > Indo-European > Old English > Dictionary > sēo

N (fem)

The pupil, apple of the eye

Source: Ringe 2014:316, https://bosworthtoller.com/27442
originates from: PWGmc *sehwā "pupil (of the eye)" (sehwā > sehwǣ > seohwǣ > seohǣ > seohæ > sēo) through pwgmc-to-oe
(source: Ringe 2014:316)