also: ごくちょうしんせい
noun
hypernova
Astronomical term for an extremely energetic supernova, more powerful than a typical supernova.
極超新星は、通常の超新星よりもはるかに明るい爆発現象です。
A hypernova is an explosion phenomenon far brighter than an ordinary supernova.
超新星 is a supernova; 極超新星 is a hypernova, a more extreme and rarer event.
Compound of 極 (extreme) + 超 (super) + 新星 (nova). The term is a direct calque of English 'hypernova'.