The three different names are:
(i) Discrete orbit It is called so because electrons revolve in certain distinct path and not just in orbit.
(ii) Energy level (energy shell) The energy associated with different orbits (with which electron revolves) is distinct for each orbit, hence it is called so.
(iii) Stationary state Since, the energy associated with an orbit is fixed. Hence, the electron revolving in a particular orbit have stationary energy. That’s why, orbits also called stationary state.