眸 is a literary and poetic word for the eye, rarely used in everyday spoken Chinese. It is common in novels, poetry, and song lyrics to evoke depth and expressiveness.
Eye radical on the left, the indexing radical. It anchors 眸 firmly in the sight family with 看 look, 睛 pupil, 瞳 pupil. The whole character means 'pupil of the eye', and the radical contributes the literal organ.
Right side 牟 supplies the móu reading exactly. Standalone 牟 originally pictured an ox lowing, then drifted to 'to seek'. Here read it purely as a sound clue — its semantic ox-and-cry image plays no role in the meaning 'pupil'.