Q: I recently came across a blogger’s statement that “there is a plethora of entries” for derogatory terms in dictionaries. My ear tells me it should read “there are a plethora of entries.” Am I right?
A: You’re right—and so is the blogger.
“Plethora” is a singular noun, like “plenitude” or “abundance,” so it’s quite normal to write “there is a plethora of,” no matter what comes after “of.”
However, it’s also quite normal to use “plethora” with a plural verb like “are.”
It all depends on whether the writer views the plethora as a collection of things or as the things in the collection.
This is called notional agreement—agreement based on a writer’s meaning rather than on grammatical form.
As Merriam-Webster’s Dictionary of English Usage explains, when the subject of a verb is “a plethora of followed by a plural noun,” then “notional agreement holds sway.”
“Writers who view the plethora as a lump use a singular verb; those who view it as a collection of discrete items use a plural verb,” Merriam-Webster’s adds.
So the writer of your sentence viewed “plethora of entries” as a “lump” rather than as the “discrete items” making up the lump.
“Plethora” has an interesting history in English. It first showed up in 16th-century medical usage, where a “plethora” meant an excess of fluid in the body, especially an accumulation of blood.
Not until the 17th century did “plethora” begin to acquire more general, nonmedical meanings.
In both medieval Latin and ancient Greek, plethora meant fullness, medically or in general, according to the Oxford English Dictionary. Greek verbs meaning to fill or to be full are the ultimate source.
The French adopted the medical term (as pléthore) in the 1530s. The English “plethora” may have been influenced by French or it may have come directly from Latin or Greek.
At any rate, the earliest OED example of “plethora” in English is from John Banister’s A Needefull, New and Necessarie Treatise of Chyrurgerie (1575). We’ve inserted medical definitions in the citation:
“In curing these kyndes of Ulcers, the causes must first be diligently searched, to witte whether it be Plethora [excess of fluids], Cacochymia [diseased fluids], or Cachexia [wasting].”
The medical sense of “plethora” has lasted into our own time. Here’s a modern OED example: “patients with congestive heart failure and inferior vena cava plethora” (from the journal Clinical Cardiology, 2000).
The figurative use of “plethora” as a glut of something bad began turning up in the mid-1600s. Here’s an example from Joseph Beaumont’s drama Psyche (1648):
“Whose never-failing Virtue did displace / Griefs vast Plethora which had her opprest.”
In the early 1800s, the figurative sense began mellowing and by the end of the century “plethora” was appearing “more usually” in neutral and positive ways, according to the OED.
Now, the dictionary says, it usually conveys a “neutral or favourable sense: a very large amount, quantity, or variety.”
Here’s a positive example from a fashion article in the August 1882 issue of Ballou’s Monthly Magazine (Boston): “There is a perfect plethora of white and twine-colored thick muslin.”
In this sporting example from the Encyclopædia Britannica of 1911, the word is either neutral or positive: “Of [yacht] races there was a plethora; indeed no fewer than 400 matches took place.”
Finally, here’s a clearly positive example from The Long View, a 1956 novel by Elizabeth Jane Howard: “An attractive woman will automatically collect a plethora of men.”
Some usage commentators still insist that a “plethora” is not just an abundance, but an undesirable overabundance. However, a plethora of historical evidence contradicts this.