Exactly What It Says on the Tin, this is a character who has no name. While No Name Given is a narrative trope where a character has a name but is not referred to by name within the work, this character either never received a name or has long-since forgotten/discarded it. They frequently get a placeholder that is some variation of "Nameless" or something similar since referring to a character "hey you" gets old.
Often a sign of Blue and Orange Morality to some extent, since having a name is necessary to function in society. As such, it's common for free spirits Walking the Earth to not have a name, or for members of a Hive Mind without individual identities. Also frequently the case with amnesiacs, though unless they specifically choose to remain nameless they usually get a placeholder name.
In Sword of the Stranger, the closest thing the ronin gives for a name is "Nameless Red Devil." Kotaro even starts calling him Nanashi, which translates directly to "Nameless".
Trowa Barton from Gundam Wing was separated from his family as a baby and raised by a band of mercenaries, who never named him. He remains nameless his entire life until the eve of Operation Meteor, when he lifts the moniker of the man originally trained to pilot the Gundam Heavyarms. After Endless Waltz, he considers himself nameless once more, until his friends convince him to keep it.
Of course, early on in the show, it's demonstrated that he still hasn't fully accepted the new name:
Trowa: Battle Record 001, pilot's name...let's go with Trowa. Trowa: I don't have a name. If you must call me something, call me Trowa Barton.
The Creepy Child in Berserk is who is highly insinuated to be Guts and Casca's child in some spiritual form has no name. This is due in part because he is voiceless and because he was never properly given a name upon his "birth." So we just call him "Guska."
"Scar" in Fullmetal Alchemist. When Yoki asks Scar's name, Scar responds that to Ishvalans, a person's name is the most important thing; the name is regarded as a gift from God. So Yoki asks again, and Scar's response is "I threw it away. I threw away my own name." Yoki doesn't dare ask him again. At the end of the series, he still refuses to give his name and says you can just call him whatever you want to.
In the 2003 anime version, Scar's name still isn't given. It goes so far as to name his last episode, in which he died, "His Name Is Unknown." Just before he dies, Lust asks him his name, and he answers that his body once had a name, but "that person died a long time ago." Lust, who'd only called him "scarred man" up to this point, finally uses the "name" Scar as he dies: "Goodbye...Scar."
In the "Planet Hulk" storyline one of the members of Hulk's group of True Companions is a Brood queen, who don't have names. She becomes known as "No-Name of the Brood."
In Dreamwave's Transformers comic series "The War Within: The Dark Ages", a character is introduced who is only ever referred to as "the Fallen," as his name was taken away from him by his fellow Transformers after he betrayed Primus and sided with Unicron. This is especially significant since Transformer names are not only personal labels, but usually define their entire purpose, personality, and/or function. (In the novel "Transformers Exodus", his original name is given as "Megatronus Prime").
In the original Marvel run of Transformers, there was a Transformer personally made by Primus (the Transformer version of God) known only as "the Last Autobot."
Batman villain Ra's Al Ghul actually qualifies. His "name" is actually his title, as he has long since discarded his name.
In Immortal Iron Fist, the ninja-servant girl who is Orson Randall's daughter was never named, due to rather restricted freedoms caused by her society's caste system. According to her, she'll have made a name for herself by the time Danny sees her again.
V from V for Vendetta qualifies. (S)He states: "I do not have a name. You can call me V"
Tin's girlfriend in Metal Men wasn't given a proper name, and was often called "Nameless".
In The Metabarons, the last Metabaron actually doesn't have a name at all.
In his backstory, Hancock lost his memory and with it, his name. He eventually adopted the name "Hancock" after someone asked for his signature (his "John Hancock") and assumed it was his name.
The viewpoint character of Hero, played by Jet Li, goes by "Nameless". In this case, it is a sign of humility.
In Warm Bodies we're told by the zombie main character at the beginning:
R: I wish I could introduce myself, but I don't remember my name anymore. I mean, I think it started with an 'r' but that's all I have left. I can't remember my name, or my parents, or my job... although my hoodie would suggest I was unemployed.
All Daleks in Doctor Who are nameless due to them being "pure" and so similar that they're effectively hiveminds. There are very specific exceptions, however.
In the backstory of Star Trek: Deep Space NineShapeshifter Odo was originally called "unknown sample" in Bajoran but the Cardassian overseeing the project gave it the closest approximation in Cardassian instead: "odo'ital," which translates literally as "nothing".
From the same series, the Changeling species does not use names. The one who oversees the war in the Alpha Quandrant is content to be referred to as "the female Changeling" and explains to Odo that they have no need for names among themselves, as they exist naturally in a liquid "Great Link."
The song "Horse with No Name" by America involves a journey through the desert... on a horse with no name. This juxtaposes the lyrics which claim that it's actually easier to maintain your identity on your own since no one is around to influence you.
Given its popularity with pieces involving wandering samurai, this trope shows up in Way of the Samurai, where 'Nameless' is the default name given to the player's ronin character. You can always choose to change it, but seeing as how the player is apparently some kind of amnesiac swordsman, it fits.
King of Fighters has a character literally named Nameless, presumed the last clone made by NESTS, and thus didn't have enough time to develop a legitimate name.
The Nameless One from Planescape: Torment. He actually had a name, but due to his amnesia he can't remember what it is. He can eventually relearn his name; however, the player can't.
In Phantom Dust, if you reject all the name choices you're given at the start of the game you will be called Nanashi (Japanese for "nameless") instead.
Not a character, but a game itself: Nanashi no Game's title translates as "The Nameless Game."
Forgotten Worlds: Both player characters are only known as the "Nameless Ones". This is kept in their cameo appearances, usually going by the moniker of "Unknown Soldier" followed by 1P/2P to identify between them. The Japanese sources have slight variations at times, like "Nameless Super Soldier". The Mega Drive Japanese manual also refers to the 2P soldier as "Mohawk Man".
Ōkami has a minor character who lives next to Hana Valley whose text boxes say "Nameless Man".
Every denizen of the shovel-beam-powered hamlet in Blank It. In fact, they take pride in their namelessness, and anyone who is given a name is immediately rejected from the society. Here it isin action.
In Knights of the Dinner Table, Dave once created a character with no name. After struggling to work out what to call him, the other characters started referring to him as 'Monkey Boy'. Eventually getting sick of this, Dave comes up with a symbol to represent the character, and the whole thing quickly turns into The Trope Formerly Known as X.
In Earthsong, the leader of Haven's Guard is unique for remembering her entire past except for her name. She goes by Nanashi, which is Japanese for "no name."
In Digger, a certain hyena had his name "eaten" by his tribe and exiled, a punishment that makes him an unperson in their eyes. He considers his name to be gone, and we never find out what it was; however, the protagonist gives him the new monicker "Ed", which he gratefully receives.
Gargoyles traditionally do not have individual names, referring to each other by their relation. Goliath took a name solely because he was essentially a liaison to the humans, who found their namelessness to be odd and confusing. The members of the Manhattan Clan do take names at the beginning of the series, however, as they wish to interact more with the human world.
Five hats means that five tropers think it is ready to publish.
You are saying that you think this draft is ready to be published. That means the description is not ambiguous,
it doesn't duplicate an existing trope, there are at least three examples, and the title makes sense.
Is that what you meant to do?
You are saying this draft has a ready-to-publish hat it does not deserve and you are taking it back.