Is "Data" Singular or Plural?

People will argue about this one.

Charles Carson, Writing for
6-minute read
Episode #139


We've received several requests to address Latin plurals, so today we're going to tackle a tricky one. A listener called with this request:

Hi, Grammar Girl. This is Adam from Peoria. I was wondering if you could go over the usage of the word data, as in The data are correct or The data is correct. Thanks.

The question seems easy enough: is data singular or plural? Unfortunately, the answer is that both usages are standard (1). However, before we can address this fully, we need to review a couple of linguistic concepts.

Mass Nouns Versus Count Nouns

As you may recall, back in episode 54 we reviewed the differences between count nouns and mass nouns so we could explain why grocery store signs should read 10 items or fewer instead of 10 items or less. Count nouns are used for objects that can be counted; that is, they're distinct objects that can be numbered. For example, in my refrigerator there are eggs, apples, and lemons. These are all count nouns. Count nouns can be singular or plural, and when you use them as the subject of a sentence, the verb must correctly reflect that number, as in The last apple IS on the bottom shelf or The eggs ARE fresh.

Mass nouns, on the other hand, are used for things that don't have a natural boundary and can't be counted. Also in my fridge are butter, iced tea, and bacon. These are all mass nouns. Mass nouns always take a singular verb, as in The iced tea IS already sweetened and They say bacon IS bad for you, but I love it.*

How Many or How Much?

An easy way to tell these two types of nouns apart is to ask yourself how many or how much. If it makes sense to ask how many there are of a noun, as in how many cars or how many people, then it's a count noun. If, however, it makes more sense to ask how much there is of a noun, as in how much butter or how much rain, then it's a mass noun.†

The use of many and much parallels the use of fewer and less: many and fewer are used with count nouns (like items in a grocery cart) and much and less are used with mass nouns, like tea or bacon.

Next: How Many Data or How Much Data?