The word "回眸" is formed by combining the character "回", which means to turn back or return, with the character "眸", which refers to the pupil or the eye itself. In this compound, "回" acts as a verb modifier indicating the direction of the action, and "眸" serves as the object, resulting in a literal meaning of "to turn back the eyes" or "to glance back". The formation directly derives from the semantic contribution of each character without additional linguistic elaboration.