WandaVision, proving that the codename stuck. Still, the MCU never clarified how the Captain Marvel moniker came about to begin with.

Related: What If... Episode 7 Cast Guide: Every New & Returning MCU Character

In What If...? episode 7, Carol Danvers formally Captain Marvel since after her solo film's era, which was set roughly 15 years before the events of Phase 1.

While the exact origin of the name Captain Marvel still hasn't been revealed, the roots of how it came about occur late in Captain Marvel. After their victory over Ronan the Acc (Lee Pace) and Yon-Rogg (Jude Law), Carol Danvers and Nick Fury washed dishes together in Maria Rambeau's (Lashana Lynch) kitchen. Fury mispronounced the name of Carol's mentor, Mar-Vell (Annette Bening), and when Carol corrected him, Nick responded, "Marvel sounds a lot better" before he launched into a rendition of "Please Mr. Postman" by the Marvelettes. It's very possible Danvers never forgot that conversation and she used Fury's suggestion as the basis to invent her superhero name.

Assuming What If...? episode 7's indication that Carol Danvers named herself Captain Marvel holds true in the mainline MCU as well, then it would make sense that the rest of the Avengers learned her codename at some point after she returned to Earth to answer the call of Fury's beeper. The Avengers only called Carol "Danvers" in Avengers: Endgame but the superheroes generally eschew using each others' codenames and prefer to call each other by their real names. Captain Marvel's legend on her own homeworld was then cemented by her performance in Endgame's battle against Thanos.

Considering that, it makes sense that fanboys like Spider-Man and FBI Agent Jimmy Woo (Randall Park) enjoy calling Carol Danvers "Captain Marvel," a name that makes her sound appropriately larger than life. But if Marvel's What If...? episode 7's hint does hold true in the MCU's Sacred Timeline, it was likely Carol Danvers herself who coined the Captain Marvel name after she was influenced by Nick Fury's savvy ear for branding.

Next: Every MCU Easter Egg In What If...? Episode 7

Marvel's What If...? streams Wednesdays on Disney+.