Alex P. Keaton
Sherman T. Potter
Maxwell Q. Klinger
We all know the initials but does anybody know what they stand for? 
I know the “T” in James T. Kirk is Tiberius but the others have always made me wonder.
Anybody?
If memory serves, Larry Gelbart once said the “T” in Potter’s name was like the “S” is Harry Truman’s. In other words, it stood for nothing.
Sir Rhosis
Bullwinkle J. Moose’s middle name is said to be Jay (as in Jay Ward); I’m guessing the same is true for Rocket J. Squirrel.
I don’t know any of the others, but speaking of Alex Keaton… the “J” in Michael J. Fox stands for… Andrew.
Actually, Andrew is Mr. Fox’s real middle name. He adopted the initial “J” as a tribute to the great character actor Michael J. Pollard. Or so I’ve heard…
Sir Rhosis
Oh, and how about Maynard G. Krebs?
I learned on this very board that the cop from the 80s with the puffy hairpiece was named Thomas Jefferson Hooker.
Sir Rhosis
But what did the R stand for in the episode Where No Man Has Gone Before?
^^Ruh-roh (to quote Scooby Doo). Though I don’t read ST novels, I’ve heard that an author named Peter David ret-conned this as a joke between Kirk and Gary Mitchell, who sometimes derisively called Kirk “Rhinoceros.” This may be a Trek urban legend, though.
Trek fans can explain ANYTHING Right, Aesiron?
Sir Rhosis
I’ve heard he had to change because there was already a Michael A. Fox and he didn’t want to be confused with him.
^^You’re right, but still, did he choose J for the reason I remembered?
Sir Rhosis
Oddly enough, yes.
That’s just weird. Pollard was always such a creepy troll-like guy.
Probably not so much that he didn’t want to as he wasn’t allowed to use the name of another actor. I’m fairly sure it’s a union rule (Screen Actors’ Guild?). That’s why these days you get a lot of initialed or three-name actors and actresses. All the common names are already taken, so Sam Jackson has to be Samuel L. Jackson.
What about Kermit T. Frog, roving reporter?
Probably the same middle name as Crow T. Robot.
^^^Yes, both of those two also had the middle name of Tiberius… 
Sir Rhosis
__
What I remembered hearing was that he couldn’t simply be Michael Fox, because there was another one. I believe that was this Michael Fox. So he had the choice of using his first name, middle initial and last name, but didn’t want to be Michael A Fox (as in Michael, he thinks he’s a “fox”). According to the bio on IMDb:
"According to an interview with Fox, he originally decided to use the middle initial J instead of his own A because he didn’t want teen magazines to use headlines such as “Michael, A Fox!”
Ernest G. Bilko - he occasionally said it stands for Greedy, but I don’t know of any full name.
And since we’re using actors as well as characters, there’s Harry H. Corbett.
(Note to Americans - he’s the star of Steptoe And Son, a British comedy that was remade as Sanford And Son. )
He said the H stands for “Henything you like.” He added it to distinguish himself from the pupeteer Harry Corbett.
Bartholomew J. Simpson-- The J is for Jojo. If I recall correctly.