Marvel’s Merc with a Mouth, Deadpool, has an instantly iconic superhero name that works well for a character whose overly violent tendencies and constant fourth-wall-breaking humor define him as Marvel’s go-to mercenary for hire. When fighting alongside The Avengers during the epic Thor-centric comic event, War of the Realms, Deadpool’s time on the roster gave him yet another nickname, one that succinctly and accurately describes him as the murderous wise-cracking guy he is.

https://screenrant.com/deadpool-codename-avengers-nickname-op-ed/