It
is common usage to refer to an electron as being "in" an orbital even though
an orbital is but a mathematical function with no physcial reality. To
say an electron is in a particular orbital is meant to imply that the electron
is in the quantum state which is described by that orbital. For example,
when the electron is in the 2s orbital the hydrogen atom is in a
state for which n = 2 and l = 0.