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da·ta (dātə, dătə, dätə)
pl.n. (used with a sing. or pl. verb)
1. Facts that can be analyzed or used in an effort to gain knowledge or make decisions; information.
2. Statistics or other information represented in a form suitable for processing by computer.
3. Plural of datum.

[Latin, pl. of datum; see DATUM.]

Usage Note: The word data is the plural of Latin datum, "something given." In English, most notably in scientific usage, this plural usage is still common, as in this example: "Eventually, his data suggest, a tumor's ... alterations give rise to mutant cells" (Janet Raloff). But data is also standard in denoting a singular mass entity (like information), especially in writing for a more general audience: "Before data is transmitted in bulk around the internet, it is routinely compressed to reduce redundancy" (Richard Dawkins). "Goodall ... wanted to get as much data as possible from her animals before she had to leave them" (Elizabeth Royte). · In our 2005 survey, 66 percent of the Usage Panel accepted the use of data with a singular verb and pronoun in the sentence Once the data is in, we can begin to analyze it. Fully 92 percent accepted the sentence We have very little data on the efficacy of such programs, the same percentage that accepted the use of data as a plural noun. (Note that the quantifier very little, like much in the last quotation given above, is not used with plural nouns such as facts or results.) The percentages in the 2005 survey represent significant increases over those of our 1988 survey, making it safe to say that singular data has become a standard usage.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.

Indo-European & Semitic Roots Appendices

    Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

    Indo-European Roots

    Semitic Roots

    The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.