Inferno (インフェルノ) is a medium-scale magic that works by dividing the target area into two sections and decreasing the kinetic and rotational energy of all objects within one section and this surplus energy can then be released into the other section in the form of heat. This way, conservation of energy is still maintained while applying the principle of reverse entropy from thermodynamics. 
Occasionally, this magic serves as a test for A-Rank Magicians, but due to its difficulty, many are unable to accomplish the employment of this magic. A testament to Miyuki's skill is shown by the fact that she can use this with ease.
Inferno (Italian for "Hell") is the name of the first part of the 14th century poem, the Divine Comedy, by Dante Alighieri. One of the most well-known, well-referenced pieces of work today, it describes in great detail the poet's vision of what hell would be like.