Q: Why isn’t one wisteria a wisterium? Did the Romans ever refer to a single wisteria plant as a wisterium?
A: The ancient Romans may have never seen the flowering vine, since the various species of the genus Wisteria are native to the US, China, Japan, and Korea.
In fact, the letter “w” didn’t even exist in classical Latin. The Romans used the consonant “v” or the vowel “u” in writing to represent the “w” sound. There was no “v” sound in classical Latin.
The English botanist Thomas Nuttall named the genus Wisteria in 1818 in memory of Caspar Wistar, an American professor of anatomy who died that year.
So why did he spell it Wisteria, not Wistaria?
An editor’s note in the July 1898 issue of Meehan’s Monthly Magazine, a horticultural journal, says Charles J. Wister, a friend of Nuttall and a relative of Wistar, once asked the botanist to explain the spelling of the genus.
Wister, an amateur botanist, called Nuttall’s “attention to the fact of his having named the plant in honor of the eminent professor, notwithstanding that he spelled his name with an a,” according to this account.
“Nuttall said that he was quite aware of that, but since the families of Wistar and Wister were one, and that Wisteria was more euphonious than Wistaria, he had preferred and adopted the former,” the editor’s note concluded.
The magazine gave only “a subscriber” as the source. Wister, who died in 1865, wrote a memoir, but we haven’t been able to find a full-text version online.
Although the common name of the plant is sometimes spelled “wistaria,” the genus is listed as Wisteria in the International Code of Botanical Nomenclature.
Nevertheless, the earliest example of the plant’s name in the Oxford English Dictionary uses the “wistaria” spelling.
Here’s the citation, from The Suburban Horticulturist, an 1842 book by John Claudius Loudon: “Vines, roses, Wistarias, or other luxuriant climbers.”