1. necro - Noun
2. necro - Verb
(Internet) To make a new post to a forum discussion that has been dormant for a long time, making the thread visible in the list of active topics; to bump.
Sorry to necro a comment from three years ago, but …
(Internet, video games and card games slang) To practice necromancy; to bring back from the dead.
necro (plural necroes or necros)
(Internet, video game and card game slang) Necromancer.
Meanwhile, thanks to Ritsu's Necro Pyro ability, she has turned all of the corpses in the Nether into Infernals that she can explode at any moment. Source: Internet