Cyclic Trope

This is a Trope that goes through a circular pattern of change, eventually returning to its original form after several iterations.

Like this: "Fat Guys Are Jolly" gets subverted over time to "Fat Guys Are Kinda Sad And Pitiful". After a while at that value, the audience is expecting "sympathetic" Fat Guys, so it gets subverted to "Fat Guys Are Mean And Greedy". Once expectations are out there for evil Fat Guys, it gets subverted back to "Fat Guys Are Jolly".

Most cycles are bipolar, though, oscillating back and forth between two opposites that mutually subvert (or invert) each other.

See also Fleeting Demographic Rule, Popularity Polynomial. Compare and contrast with Undead Horse Trope, Evolving Trope.

Remember, Examples Are Not Recent.

Some tropes that are cyclic:

 * 3D Movie: Started out as "the next big thing", then thrown aside and treated with disdain. Now, it's "the next big thing". This has already happened twice before (first in the 1950s and then again in the 1980s), as each time the Technology Marches On it's revived, gets a couple of years in the spotlight, and then everybody decides it's still not worth the trouble. It seems to have repeated again, with 3D technology becoming less frequent in movies (though the fact that very popular and non-gimmicky movies like Avatar and Toy Story 3 have used it and drawn in more ticket sales as a result means that the trend probably won't disappear entirely).
 * Action Girl (status/appeal cycles between Hot Amazon and No Guy Wants an Amazon)
 * American Dream (cycles between optimistic and pessimistic depending on the economy and general state of the union)
 * Cowboy Cop (fluctuates between protagonist and antagonist depending on how much "traditional" cops are respected)
 * Deconstruction (deconstructing a genre, then deconstructing the deconstruction)
 * The Fair Folk, as well as probably most cases of Our Monsters Are Different
 * Female sexuality: since the dawn of time, humans have been cycling though the ideas that All Women Are Lustful and All Women Are Prudes.
 * Hair Colors (Hair of Gold to Dumb Blonde to Blondes Are Evil and back again, with brunette always being the Foil for wherever blonde is today, and red hair being a more Hot-Blooded version of brunette.)
 * Hipster: recurring definition with every generation rejecting the previous batch.
 * Love Interests: cycles between Proper Lady and Well, Excuse Me, Princess! and every degree in between; characters are Colour-Coded for Your Convenience, as they cycle respectively between blonde and red-haired or brunette.
 * Morally-Bankrupt Banker: Popular during banking crises and economic downturns.
 * Never Say "Die"
 * Our Vampires Are Different: Vampires cycle between soulless predatory monsters and angst-filled romantic woobies.
 * Goes hand in hand with Looks Like Orlok. First they did, then they didn't, then they did again, and now they don't again. And given the attitudes towards the modern vampire, it's only a matter of time until they look like Orlok again.
 * Patriotic Fervor (cycles according to world events)
 * Sliding Scale of Idealism Versus Cynicism: Interestingly, this tends to parallel the political and economic climate of the society generating the works that feature the Trope.
 * Also related to whatever seems rare and different from the norm, e.g., when any given superhero has an 90% chance of being a troubled, brooding Nineties Anti-Hero, Capes start becoming fascinating to the point of being edgy.
 * Spy Fiction: The world's current political system determines whether or not Tuxedo and Martini James Bond-ish films or Stale Beer Post Nine Eleven Terrorism Movies get respect from the audience.
 * Token Minority into Token White
 * The Vamp (cycles between blonde and brunette)
 * Super Robot Genre: The entire genre goes through cycles of Deconstruction and Reconstruction. To give a very simplified version, starting with the Trope Maker: Mazinger Z --Deconstruction--> Mobile Suit Gundam --Reconstruction--> Gunbuster --Deconstruction--> Neon Genesis Evangelion --Reconstruction--> GaoGaiGar
 * Sword and Sandal: Hollywood's on-off relationship with them.
 * Unfortunate Ingredients: In the '80s and '90s, sugar was the greatest evil. Now, many ads tout the presence of "real sugar" in their goods because nobody trusts artificial sweeteners or high-fructose corn syrup (both are made up of glucose, i.e. blood sugar, and fructose, i.e. fruit sugar, instead, but while sucrose, i.e. table sugar is 50% glucose 50% fructose, corn syrup varies between 53% and 90% fructose, with the rest being glucose).
 * Western Terrorists (the ethnicity of terrorists cycles according to world events and frequency of use)
 * Romanticism Versus Enlightenment: the mother of all Cyclic Tropes -- at least, according to some. It is said that there are two trends in culture, coming in waves and supplanting one another: the orderly Apollinian, and chaotic Dionysian. Apollinian Enlightenment is followed by Dionysian Romanticism, which is followed by Apollinian Positivism or Realism... and so on.