I am the Kat that Walks By Itself

Spells are wishes, curses, blessings, prayers; a plain direction or request, spoken or willed. This may need to be in a specific language, particularly for prayers.

Are you familiar with the system used in the Ars Magica RPG? If not, quick summary.

Spells are defined by five techniques and ten forms. The techniques are verbs, all in Latin, such as Creo (I create), Muto (I change), Rego (I rule). The forms are nouns, such as Animal, Corpus, Ignem, etc. There are thus fifty possible combinations, such as Creo Ignem (to create fire), Muto Corpus (to alter a body) or Rego Animal (to control an animal).

Each combination is not, however, a spell, rather a category into which various spells naturally fall. The techniques and forms are skills in manipilating different applications of magic.

I know you've played D&D in the past, I don't what other RPG experience you have, but RPGs are the obvious place to go if you want to look up different ways of doing magic.