When used to reference the element with atomic number 94, plutonium is an uncountable noun and therefore has no plural form. In MANHATTAN .45, where Dorothy gives the term a second meaning as a type of cocktail, it is now reasonable to ask, as did she, what the plural should be. Invoking the grammatical principle of declension—meaning different noun forms, depending on context—and taking as a template the homoeoteleutonic (same ending) word stadium—which according to both Merriam-Webster and the OED is pluralized as stadiums in everyday usage, or stadia in strict academic or formal usage—both forms would be correct. So, “I prefer Plutoniums,” when, say, casually comparing cocktails, but “Two Plutonia, please,” when ordering them at the Plaza Hotel’s Palm Court.
The Plutonium cocktail was invented by the author. Here is the recipe:
☢ 4 oz. Physic Gin (distilled in Oxford using botanicals foraged from the plot across from Magdalen College, originally the “Physicke Garden”—hence the gin’s name—but now known as the Oxford Botanical Garden). If Physic Gin can’t be obtained, The Botanist, widely available, is a good substitute.
☢ 1 oz. L.N. Mattei’s Cap Corse blanc (don’t substitute another aperitif; the quinine in Cap Corse is what makes the cocktail radioactive)
☢ A dash of Lavender Bitters (the Original Lavender Bitters from scappysbitters.com, a Seattle maker, is a good choice)
☢ Shake well with plenty of ice and serve straight up with a generous twist. Serves two
An historical oddity: according to the OED, the term plutonium was first used in 1816 by the scientist Michael Faraday. How could this be, over a century before plutonium was discovered in 1941 (or, more accurately, when Glenn Seaborg first synthesized plutonium in a Berkeley cyclotron, since it doesn’t exist in nature)? Seaborg, following the example of uranium, named the new element in honor of the then recently discovered planet, Pluto.
In 1816, Faraday referred to “plutonium” in a letter to Edward Daniel Clark, but apparently he meant the element lately discovered by Humphry Davy, barium.1
1. “Faraday0067a,” in Ɛpsilon: The Michael Faraday Collection accessed on 10 June 2026,
https://epsilon.ac.uk/view/faraday/letters/Faraday0067a
MANHATTAN .45