pupil: [14] Latin pūpus and pūpa meant respectively ‘boy’ and ‘girl’ (pūpa was applied by the Swedish naturalist Linnaeus to ‘chrysalises’, the underlying link being ‘undeveloped creature’, and English adopted it as pupa [19]). The diminutive derivatives pūpillus and pūpilla denoted ‘orphan’, a sense which remained with pūpill- as it passed via Old French pupille into English as pupil. ‘Person being taught’ did not emerge until the 16th century.
The application of the word to the ‘black aperture in the eye’, which reached English in the mid-16th century, goes back to Latin pūpilla, which was also used for ‘doll’ – the notion being that if you stand close to someone and look into their eyes, you can see yourself reflected in the pupils like a little ‘doll’. => pupa, puppet, puppy
