A typhoon is a mature tropical cyclone that develops between 180° and 100°E. A severe typhoon has winds of at least 80 knots.
On another hand, a super typhoon has winds of at least 100 knots, which is 120mph. The US Joint Typhoon Warning Center, however, places the term super typhoon as something “that reach maximum sustained 1-minute surface winds of at least 130 knots”, which 150mph and 65 m/s.
In the scientific literature, the unofficial term is intense hurricane.
This documentary explains the phenomena, and the six conditions required for formation, which are warm sea surface temperature, atmospheric instability, high humidity in the lower to middle levels of the troposphere, and more.