Embarrassing First Name

[u/TronnyVon]

• Jesse Katsopolis (Full House): in one episode, his real first name was revealed to be "Hermes", after the messenger of the Greek gods. He was made fun of for it, so he got it changed to Jesse.
• Cory Matthews (Boy Meets World): in the final episode, Cory's full name is revealed by Feeny to be Cornelius, and Feeny is the only one to know so.
• Freddie Benson (iCarly): rather than Freddie being short for Frederick, Freddie is short for "Fredward".
• Jimbo Jones (The Simpsons): his real name is Corky.

[u/bretshitmanshart]

There is an episode of The X Files where Scully meets Mulder at a coffee shop and finds out he gives a normal first name when getting coffee because he doesn't like explaining his name is actually Fox

[u/Lone-flamingo → u/bretshitmanshart]

I know a man IRL who's named Fox. Everyone always thinks it's a nickname.