The Namesake

Suppose you go see a film called The Boat. The movie starts and it takes place as far away from a body of water as is possible. No boats. An hour can pass and you won't see a single boat. But just when you were thinking "maybe it's a Non-Indicative Name", a huge sailing vessel is revealed to be what everything was revolving around. Expect to hear someone in the theater go, "Oh, that's what it was!" This trope is similar to a Title Drop except that a character need not say it aloud.

A namesake is the thing within a story that the story itself is named after. It could be a character, a place, an object, or indeed a metaphor. Often, the namesake is rather obvious (Romeo and Juliet is obviously named that way because there's a character called "Romeo" and another called "Juliet"; The Time Machine obviously includes a machine to travel through time) but sometimes, authors (or film studios) want to use titles that draw attention, and that's when the namesake may not appear until the end of the story, or might indeed only be a metaphor for a certain situation in the story which doesn't become clear until the end. In short, this becomes a trope when the reason why the book/movie/chapter/episode/etc. is called the way it is, isn't revealed to the audience until near the end; regardless of whether the characters knew about it all along or not. If book/movie/chapter/episode is named after a pivotal plot point rather than an actual person/place/thing, then it's a Spoiler Title.

Examples below should be stories where either what the title "promised" wasn't delivered until rather late in the story, or the title seemed non-indicative, and later was revealed to be physically in the story. Please do not put stories whose name was intentionally misleading all along, with the title thing never actually appearing.

Sometimes this is turned on its head when titles that the audience expects to refer to a metaphorical namesake become literal. As an example, if you haven't read Asimov's short story "Nightfall", you'll probably think the title is a metaphor for the situation the characters find themselves in, similar to Stephenie Meyer's use of the title Twilight. Asimov's story, in fact, revolves literally around an iminent sunset, which is an event the characters have never experienced.

May be lampshaded if, once the namesake finally appears, a character asks, "Why do they call it that?" usually immediately after the Title Drop

Not to be confused with Namesake Gag nor the book and film entitled The Namesake. In literary circles this is called an Eponym, a term also used to refer to a Character Title.

Anime and Manga

 * Tengen Toppa Gurren Lagann: The title refers to the final form of Gurren Lagann, which doesn't appear until the last episode. Averted in the English dub, the title is simply Gurren Lagann.
 * Gundam series tend to be named for the protagonist's Humongous Mecha, but there are a few noteworthy exceptions. The most prominent is Gundam Seed, which is named for an in-universe theory about an innate factor that lets them advance to the next stage of evolution. Naturally, it's possessed by the four central characters (and the protagonist of the sequel).
 * Frequently, the title refers to the protagonist's Mid-Season Upgrade rather than their original mobile suit; the Zeta Gundam, 00 Gundam, and God Gundam come to mind.

Comic Books

 * DC Comics' 52 at first seems like a reference to its Real Time format a la 24 (each issue covering the span of a week and published weekly for one year), though a number of gratuitous 52s were thrown around. Near the end it's revealed that it refers to
 * The English title for the Tintin adventure The Red Sea Sharks references an element which only shows up at the end of the story. In most other languages, this album is known as "Coke on Board", with "coke" (as in refined coal) or some variant being a code-word for.

Film

 * The Phantom Menace has an interesting title, especially compared to the self-evident titles of the other Star Wars movies. Namely, it raises the question, who is the "phantom menace"? Darth Maul, as the advertising campaign would suggest? Senator Palpatine, the mastermind behind it all who hides behind a respectable front? The Sith in general, who are supposed to be extinct? Or perhaps Anakin, who at this point is only a "phantom" of the "menace" he will one day become?
 * In the original version of The Wicker Man, the titular man of wicker isn't shown or otherwise mentioned until the very end of the movie.
 * Disney's The Princess and the Frog: Tiana, the film's heroine, only eventually becomes a princess by marriage, and the frog is actually a prince.

Literature

 * Bridge to Terabithia: The title "bridge" finally appears.
 * Harry Potter chapter titles do this quite a bit. For instance, chapter eight of Harry Potter and The Prisoner of Azkaban is entitled . This doesn't actually happen until the second-last page of the chapter.
 * Azkaban has a chapter titled "The Servant of Lord Voldemort".
 * The Hitchhiker's Guide To The Galaxy's So Long, and Thanks for All the Fish doesn't reveal its namesake until chapter 23.
 * Although those who read the first book know that.
 * Lord of the Rings: The Two Towers: The second tower is revealed quite late in the book.
 * The Nick Hornby novel A Long Way Down is about four people planning to jump off a building, so it seems clear what the title means. Except that a line near the end twists what you think The Namesake is; they ask whether they should jump, which would be the short way, or take "the long way down", that is, taking the stairs back down and moving on with life, which is literally "the long way".
 * The Brandon Sanderson novel Warbreaker's namesake is revealed on the last page.
 * Or the inside blurb of the hardcover...
 * In The Name of the Rose, it's not made clear what the title refers to until the last page.
 * Although Lloyd Alexander's Chronicles of Prydain largely averts this, the final book, The High King, plays it fairly straight.
 * The books in the second Warrior Cats arc, The New Prophecy are all named after times. In the first book, the chosen cats are told to go to the place where "the sun drowns" to "listen to what midnight tells them". At the end of the book,

Live Action TV

 * Crossed, Double-Crossed is a book shown in an episode of the TV series Charmed. Though the characters in the book generally mistrust eachother, there isn't an actual betrayal until the end; when the main characters find themselves surrounded by bad guys and the book's narrator reveals The Namesake by saying, "The couple knew they'd been double-crossed and there was no way out."
 * Several Lost episodes do this, such as "The Substitute," "Some Like it Hoth," and "Jughead." The flashbacks in "Not in Portland" depict Juliet being recruited for a job in Portland. At the very end, we learn this is actually how she was recruited by the Others. Richard tells her, "Well, actually we're not quite in Portland."
 * The titular event in The Event is not revealed until the final episode. Because the series is Cut Short, it only really gets mentioned in passing and we never see it transpire.
 * Although "Doctor Who?" is asked by many characters throughout the series, it has now become.
 * Not to mention, which doesn't take place until the end of the episode.

Video Games

 * Kingdom Hearts is named for a mysterious location that's most accurately described as "The Heart (Core) of all worlds (Kingdoms)." though in the first installment it isn't even discussed until about 85% of the way in. Its sequel reveals it halfway in and the prequel talks about it just before the last area.
 * The Legend of Zelda: Twilight Princess plays with the trope. An early Title Drop by Midna makes it appear that the second part of the title refers to Zelda herself, as the princess of a kingdom flooded with twilight. Only when the game is at least half finished is it revealed that.

Web Comics

 * Panthera: The reason for the title isn't revealed until the 19th strip, which, due to the comic being weekly and having missed an update, meant that it was revealed after 6 months! Once it was, the author was quite verbal in pointing it out.
 * Something*Positive: The title never actually appears in the strip anywhere. One of creator Randy Milholland's friends urged him to do "something positive" with his life, and the comic was the end result.