4KB invented word used in a lot of shitpost discord servers describing someone of utmost gayness possible. Someone who you typically want to avoid to prevent catching the gay and should be cautioned at any given time

n. The birth name of somebody who has changed their name. Most commonly attributed to trans people, but can be attributed to any person who has changed their name. (sometimes written as two words: dead name)

v. 1. To call somebody by their deadname.
v. 2. To out somebody's deadname to the public.