That's true! For reasons that are beyond my understanding, the Oxford English Dictionary lists pupil for 'student' and pupil for 'opening in iris' as two separate entries, despite having the same derivation. The former may not specifically mean 'girl student', but I suppose in the context of an all-girl school, it can only mean that.My dictionary says that pupil is (among other meanings) "a person who is taught by another, especially a schoolchild or student in relation to a teacher", so I thought it is close to kid.