Hane-goshi, the spring hip, gets it's name from the 'coiled spring' action of the throwing leg of the tori - although the technique certainly works best when 'sprung' in with the supporting leg.
A very difficult throw to master, it is beautiful to observe when executed properly. Another technique that the tori does not turn fully in - instead, the 'T' shape of the opponents feet used to catch that springing leg correctly.
Other versions of this throw could be classified as ko-hane-goshi, o-hane-goshi, tachi-hane-goshi. The version in this video would be the o-hane-goshi. Interestingly to Akitas members, my father (Shacho) performs more of a ko-hane, myself the o-hane, and my brother tachi-hane - which I think just goes to show that a technique often depends more on the uniqueness of the executor than it does the dependency of hitting a perfect technique.
