Entastics

The art (or science) of designing a spell so that it produces the maximum result from the minimum energy outlay: an important business for a wizard, who has to personally pay a price for every scrap of wizardry done. Just as it's smart for a computer programmer to write "tight code", it makes sense for a wizard to construct spells with no unnecessary parts or wasted energy.

The basic form of the word -- entasis, derived from an old Greek compound meaning "to stretch something out tight" -- is used by wizards to denote the specific part of the spell used to handle its energy outlay and management. (SYWTBAW et seq.)