The Falcon has the civilian name Sam Wilson. Samuel Wilson was the name of a meat packer who was allegedly the inspiration for Uncle Sam.
When the Red Skull had worked his way into the position of Defense Secretary of the United States, he used the alias Dell Rusk - an anagram as well as a reference to former real-life State Secretary Dean Rusk.
Dark Avengers: Victoria Hand, Norman Osborn's right hand (wo)man.
Deadpool: The real name of Fenway, a supporting character who is obsessed with baseball, is Homer Unn. Ironically, his nickname comes from one of the hardest ballparks to hit a homer in, due to Fenway Park's infamous "Green Monster".
Doctor Strange: Dr. Stephen Strange is not only a sorcerer, he debuted in the series Strange Tales.
DOOM is FURIOUS that Victor Von Doom, main villain from the Fantastic Four was not the very first example! Seriously, what were his parents thinking? According to the original canon, he was Roma, and they had to have it sound European. It was not uncommon in the past for Romanies to have two names, one used within their community and another used with outsiders, so his ancestors may have adopted 'Von Doom' to blend in with (the presumably Germanic-speaking) peoples around them.
The villain Diablo, real name Esteban Diablo, was supposedly a Spanish alchemist born in the 9th century (or 19th, depending on the source). His name translates to "Stephen Devil". No one could use such a surname in Spain, even less in a more religious era. Later his name was retconned to Esteban Corazón del Diablo, meaning "Stephen Devilheart" or "Stephen Heart of the Devil". Now Mom's surname is "Of the Devil"; not a great improvement. Even later, Spanish-born comic-book artists working for Marvel apparently campaigned to change the surname to "De Ablo", meaning absolutely nothing but at least that would not require an execution.
Foolkiller: The second Foolkiller's real name was Greg Salinger. He was a poet and very attuned to literature. He instructed his successor to say to his contact that he was picking up a package for Pierre, J.D. A reference to Pierre Salinger and J.D. Salinger, both of whom are also known for something literary.
Hawkeye: The villain Crossfire has the real name William Cross.
Iron Man: Tony Stark is one of the most powerful heroes in the Marvel Universe - not surprising considering that his last name is the German word for strong.
His given name, Anthony Edward, means "rich protector".
Marvel Mystery Comics: The Golden AgeTimely ComicsAngel had the real name Thomas Halloway. Thomas is the name of a saint, 'Hallowed' means something is holy or sacred. Surprisingly, he never took advantage of it. "Criminals! Know that you stand on hallowed ground... for it is under the protection of The Angel!"
Spider-Man: Otto Octavius/Doctor Octopus. Lampshaded in the second movie, when J. Jonah Jameson says "Guy named Octavius winds up with eight limbs. What are the odds?"
Sub-Mariner: Namor's name means "avenging son" in Atlantean. Avenging is all he does. His cousins Namora (avenging daughter) and Namorita (... little avenging daughter, one assumes) are less prone to ludicrous amounts of rage.
Namor is also Roman backwards, referring to the fact that Atlantis has some similarities with Rome.
The Aquaman stand-in from Rob Liefeld's Awesome Comics line was named Roy Roman — "Roy" meaning "King" and Roman being, as noted, "Namor" backwards.
A strange case: John Byrne brought Luke Cage and Iron FistBack from the Dead by revealing that they were impostors. In the process he retconned that the character Tyrone King was a preestablished villain, Master Khan. "Even the name, 'Tyrone King', means 'Master Khan'!" The original author had put the meaningful name in by pure coincidence.
Ultimate Fantastic Four: Revka Temerlune Edifex Scyros III's name literally means "The King with no Enemies" due in part to his ability to make anyone his happy slave.
Warlock (1967): Adam Warlock had his name changed to this by the Evolutionary. 'Adam' (for being the first of his kind) and 'Warlock' because "Men would fear his powers".
Magneto's long-since-not-secret-anymore identity is Erik Magnus Lehnsherr, and the "Magnus" is the only part of it that we know to be part of his birth name. "Magnus" could just refer to Magneto's awesomeness, not his magnetic powers. Though the fact that it sounds similar to his power is no doubt intentional on Stan Lee's part.
His real last name was eventually retconned as Eisenhardt - "eisen" is German for "iron."
Lehnsherr is German for "feudal lord."
Professor Charles Xavier, founder of the X-Men, though it's his fault instead of it being coincidental within continuity. He swears (depending on the era) that the name X-Men stands for "extra" power or for the X-factor gene, not his name. (Somehow, it took a villain deliberately outing him after years for people to get the hint that bald, wheelchair-bound Professor Xavier and bald, wheelchair-bound Professor X were the same guy... though there were other villains who already knew, but for various reasons had no interest in outing him.
The Vanisher's real name is Telford Porter. This is also Lampshaded in an issue of She-Hulk that revealed he has other aliases such as I.M. Ouddahere and C.U. Later.
En Sabah Nur (Apocalypse) is the first mutant, and his name is said to mean The First One. However, in our universe, it is Arabic for 'the morning light', i.e. "first light", i.e. dawn. However, though it would be grammatically incorrect by modern understanding (it should be El Sabah Nur and Sabah and Nur are more commonly girl's names), Apocalypse was born in ancient Egypt, long before the modern Arabic language existed. At least in the Marvel Universe, "En Sabah Nur" meant 'The First One' and the language only changed after he had lived for hundreds of years, if not thousands.
Emma Frost is an "ice queen", though her powers are not ice-related. (She does take over Iceman's body at one point, though...) There's also the later addition of turning herself into a diamond (frost sorta being related to ice, which doubles as a slang term for diamonds).
Cain Marko, as in "the Mark of Cain", Professor X's jealous stepbrother (aka the Juggernaut). Less well known, the Mark of Cain was meant to protect Cain from being harmed (albeit indirectly). In Marvel he's a Nigh-InvulnerableImplacable Man.
Wolverine (James Howlett). Although James later called himself Logan, then later received the nickname "Wolverine," he resembles more of a wolf than an actual wolverine, a fact to which Howlett alludes.
X-23's real name is Laura, as in "bay laurel," the leaves of which symbolize victory.
In X-Men: Evolution, Leech's real name is Dorian Leach. (In comics, he has no "real" name.) A couple other characters in this show have their names changed to resemble their codename: Avalanche/Lance Alvers (comic: Dominic Petrakis, whose powers allow for the domination of rock) and Toad/Todd Tolensky (comic: Mortimer Toynbee).
Sunfire from the Uncanny Avengers has the name Shiro Yoshida. Shiro can be translated as "Samurai male," which is fitting for a character absolutely obsessedwith honor.
Ultimate X Men: Longshot was renamed as Arthur Centino. This name is a reference to both of his creators, Art Adams and Ann Nocenti.
Hank McCoy: Boy's named Rasputin. Should have known he would be hard to kill.
Young Avengers: Wiccan. In the belief system of Wicca, emotions are believed to have power; Wiccan is at his most deadly when influenced by strong emotion. Example: he put 20 bad guys into comas when they were threatening his boyfriend.
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