Take a look at that photo above. Would you say that’s myriad dirty rubber duckies? Or do you see a myriad of dirty ducks? Up until recently, I would’ve avoided the question entirely by calling it something less controversial, like a shit-ton of old ducks. The former use has always sounded pretentious to me, but I’d seen enough outrage over the latter to assume it was grammatically incorrect.
Well, the English language is full of myriad surprises, and this fancy-sounding word is no exception. Benjamin Dreyer, vice president and executive managing editor of Random House and the author of Dreyer’s English: An Utterly Correct Guide to Clarity and Style, is here to set us straight:
Are we doing the "myriad" thing again?
Well, it was a noun before it was an adjective, so feel free to "a myriad of" to your collective hearts' content.
— Benjamin Dreyer (@BCDreyer) August 5, 2020
The word “myriad” can be used as either an adjective or a noun. You can say you’ve got myriad objections to Dreyer’s point — or you can say you’ve got a myriad of objections to it. Both are valid (well, except that he’s right).
The belief that it is more proper or a purer use of the word to only use it as an adjective is flat out wrong, Merriam-Webster says:
Recent criticism of the use of myriad as a noun, both in the plural form myriads and in the phrase a myriad of, seems to reflect a mistaken belief that the word was originally and is still properly only an adjective. As the entries here show, however, the noun is in fact the older form, dating to the 16th century. The noun myriad has appeared in the works of such writers as Milton (plural myriads) and Thoreau (a myriad of), and it continues to occur frequently in reputable English. There is no reason to avoid it.
If M-W sees no reason to avoid it, you shouldn’t either.