The Correct Singular Form Is 'Paparazzo'

In these celebrity-obsessed times the word 'paparazzi' is as ubiquitous as Brangelina-related phenomena.
The correct usage of the word is as follows:

One paparazzo - a boatload of paparazzi.

And the word comes to us from none other than the great Italian film director Federico Fellini. The source is actually his La Dolce Vita.

There is more here:

"The word paparazzi was introduced by the 1960 film La Dolce vVita directed by Federico Fellini. One of the characters in the film is a news photographer named Paparazzo (played by Walter Santesso). In his book Word and Phrase Origins, Robert Hendrickson writes that Fellini took the name from an Italian dialect that describes a particularly annoying noise, that of a buzzing mosquito. In his school days, Fellini remembered a boy who was nicknamed "Paparazzo" (Mosquito), because of his fast talking and constant movements, a name Fellini later applied to the fictional character in La dolce vita. This version of the word's origin has been strongly contested[citation needed]. For example, in an interview with Fellini's screenwriter Ennio Flaiano, he said the name came from a southern Italy travel narrative by Victorian writer George Gissing, "By the Ionian Sea." The book, published in 1901, gives the name of a hotel proprietor, Signor Paparazzo. He further states that either Fellini or Flaiano opened the book at random, saw the name, and decided to use it for the photographer. This story is documented by a variety of Gissing scholars and in the book "A Sweet and Glorious Land: Revisiting the Ionian Sea" (St. Martin's Press, 2000) by John Keahey.
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