Aliquis -

It signifies a "certain someone" or a "somebody," as opposed to "anyone at all".

or psychological texts (like Freud's discussions)? Grammatical drills ? aliquis

Aliquis (substantive) and aliquī (adjective) are declined similarly to the relative pronoun quis , with aliqua commonly used for the feminine singular and neuter plural. It signifies a "certain someone" or a "somebody,"