threadomancy 

reviving an old forum topic after many months, often simply adding nothing to the topic itself by only replying "I agree."

Poster: I think that Bush didn't actually expect to find WMDs, he was only trying to take Saddam out of power.

2 months later.

Threadomancer: I agree.

threadomancy by sdjaks April 25, 2004

Threadcromancy 

The reincarnation of old threads on forums. It comes from joining Thread and Necromancy.

Argh, stop bumping, I've had enough of all this threadcromancy.

Threadcromancy by Anon287 December 18, 2006

threadromancy 

The resurrection of a dead thread in a forum. It's a simple contraction of thread-necromancy.

In our forum, threadromancy is frowned upon.

Bob is an annoying threadromancer.

threadromancy by gorgeous_si May 19, 2004