The dictionary mentions the sense of necromancy as "magic in general" as well as the latin etymology.
Necromancy | Define Necromancy at Dictionary.com
nec·ro·man·cy [nek-ruh-man-see] Show IPA
noun
1. a method of divination through alleged communication with the dead; black art.
2. magic in general, especially that practiced by a witch or sorcerer; sorcery; witchcraft; conjuration.
Origin:
1250–1300; necro- + -mancy; replacing Middle English nigromancie < Medieval Latin nigromantīa for Late Latin necromantīa < Greek nekromanteía; by folk etymology nigro- (combining form of Latin niger black) was substituted in ML for original necro-
I was also thinking of the Arch-Necromancer Phandaal in Vance's The Dying Earth. I don't think he had anything to do with the undead. He just had the most spells.
edit: better definition
necromancy - definition of necromancy by the Free Online Dictionary, Thesaurus and Encyclopedia.
necromancy [ˈnɛkrəʊˌmænsɪ]
n
1. (Spirituality, New Age, Astrology & Self-help / Alternative Belief Systems) the art or practice of supposedly conjuring up the dead, esp in order to obtain from them knowledge of the future
2. black magic; sorcery
[(as in sense 1) ultimately from Greek nekromanteia, from nekros corpse; (as in sense 2) from Medieval Latin nigromantia, from Latin niger black, which replaced necro- through folk etymology]
necromancer n
necromantic adj
Collins English Dictionary – Complete and Unabridged © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003