[Gordis]

Originally Posted by alatar

And why did Tolkien use the word, 'necromancer?' I understand (maybe) why he didn't use wizard or witch, but why the title that speaks of communicating with the dead, that more than Sorcerer?

The term "Necromancer" for the Sorcerer of Dol Guldur was devised in 1930-ies, when Tolkien was writing "the Hobbit" - long before Tolkien invented Sauron or the One Ring.
At the time, and almost all through Tolkien's work on the LOTR, the wizards were not what they have become later - not Maiar, but mortal Men "of a noble profession", wielding sorcery and having a very long life.

Some remnants of these earlier ideas are still visible in LOTR. In the “Shadow of the Past”, Gandalf expresses a "professional” interest in the Ring: " I was professionally interested in your ring, you may say; and I still am.”

At first the Wizards were supposed to be rather numerous and common - almost like special "folk".
See this part of the LOTR prologue:

And certainly it was from Bree that the art of smoking the genuine weed spread in the recent centuries among Dwarves and such other folk, Rangers, Wizards, or wanderers, as still passed to and fro through that ancient road-meeting.

Compare it with the quote from the Hobbit:

Indeed Bilbo found he had lost more than spoons – he had lost his reputation. It is true that for ever after he remained an elf-friend, and had the honor of dwarves, wizards, and all such folk as ever passed that way; but he was no longer quite respectable.

The wizards were supposed to come from Numenor. See this quote from the LOTR ( also present in early drafts):

'Who is Saruman?' asked Pippin. 'Do you know anything about his history?' 'Saruman is a Wizard,' answered Treebeard. 'More than that I cannot say. I do not know the history of Wizards. They appeared first after the Great Ships came over the Sea; but if they came with the Ships I never can tell. Saruman was reckoned great among them

Now in “the Hobbit”, how to single out a “bad” one among numerous human sorcerers? - Referring to him as “Necromancer” implied that he used Black Magic, meddled with the spirits of the Dead- a bad thing that the other wizards didn’t do. I don’t think that in the 1930-ies it went any deeper than that.