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Browse the Medical Dictionary:: A; B; C; D; E; F; G; H; I; J; K; L; M; N; O; P; Q; R; S; T; U; V; W; X; Y; Z; #

OS

Main Entry: OS

Function: abbreviation

Etymology: Latin oculus sinister

left eye—used in writing prescriptions

Learn more about "os"

Learn more about "os" and related topics at Britannica.com

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