optics
n.
"science of sight and light," 1570s, from optic; also see -ics. Used for Medieval Latin optica (neuter plural), from Greek ta optika "optical matters," neuter plural of optikos "optic."
〔李〕[opt;-icsn.] n.光学 ←op,opt (GK ops,optos)=eye, sight 眼睛，视力
〔李〕n. 光学 [opt =sight] ←-ics [L] 表示“⋯学”