There are a number of terms that are used in s-CRY-ed.
Alter — A power that organisms can achieve and use to manipulate molecular reality in some way. The ability to use Alter power can be present from birth or attained after one has seen "the other side". The form Alter power takes differs between different organisms and can be upgraded through training and experience to the highest form of shining light and armor. An Alter can come in the form of an independent body such as Ryuhou's Zetsuei, an element such as water or blizzard, harmonious armor such as Kazuma's right arm, an intangible power such as telepathy, or a weapon such as Tachibana's Eternity Eight. However, matter must be processed in order to use the energy or resources to crystallize or create the Alter. Often, Alter users will take small chunks out of the surrounding environment to use as matter to form their Alter. The Alter user can control what matter will be used to attain the Alter.
The Light/Other Side — Reference to the other world of Alters, a place bathed in psychedelic light. One can achieve the light when encountering "the Crystal" or by exceeding the limit of their Alter through immense force of will. Those who make contact with or tap into the power of the Other Side are able to strengthen their Alter.
Refinement — Some Alters have been sent to the mainland to have their Alter powers processed, allowing them to display increases in their powers. What actually happens in the refinement process is never mentioned, but it is known to be rather random, as successfully-refined Alter users age more rapidly than normal humans. Failed refinements turn the patients into what are called Darths.
s-CRY-ed — Although not mentioned in the anime, in the manga, it's the "word of evolution." Its ability is just that: to evolve a person's Alter. In the manga, there are five instances of its use, the first by the Alter hermit that taught this to Kazuma, and then Kazuma himself. Next was Ryuhou, while joined with Scheris. Finally, Akira Mijyou uses it twice. In the last case, the evolution simply changed the shape of her Alter, while in Kazuma and Ryuhou's cases, it fused them with their Alters.