The general definition of what constitutes a felony can be found in
California Penal Code § 17(a).
A felony is a crime that is punishable with death, by imprisonment in the
state prison, or notwithstanding any other provision of law, by imprisonment
in a county jail for more than one year.
Except in cases where a different punishment is prescribed by any law of this
state, every offense declared to be a felony is punishable by imprisonment
for 16 months, or two or three years as provided in subdivision (h) of
Section 1170.