What is a synonym for fad?

Here are some synonyms for "fad", depending on the specific nuance you want to convey:

General synonyms:

* Craze

* Trend

* Fashion

* Whimsy

* Vogue

* Mania

* Rage

* Novelty

More specific synonyms:

* Short-lived: Passing fancy, fleeting interest, ephemeral trend

* Popular: Buzzword, catchphrase, sensation, phenomenon

* Overblown: Bandwagon, hype, obsession, frenzy

* Unimportant: Frivolity, caprice, whim

The best synonym will depend on the context in which you are using the word.