1) a person studying or teaching philosophy; a person who lets reason control her or his life (philosopher)
2) (of) a person studying for a degree after having received a first (Bachelor) degree (postgraduate)
3) a group studying a problem and meeting for discussion with a tutor or professor (seminar)
4) a person who is studying or training (student)
(an instance of) speculating; (a business deal as a result of) speculating
theory, guess