datum

noun

da·​tum ˈdā-təm  ˈda- 

ˈdä-

1

plural data ˈdā-tə  ˈda- 

also

ˈdä-  : something given or admitted especially as a basis for reasoning or inference

an important historical datum

This enormous expense—and considerable risk—to pick up a datum or two about geriatrics?

—Charles Krauthammer

2

plural datums, mathematics : something used as a basis for calculating or measuring

measuring the distance between datum points

… make things more efficient for those of us whose work requires a time datum.

—Robert Steinbrunn

Is data singular or plural?: Usage Guide

Data leads a life of its own quite independent of datum, of which it was originally the plural. It occurs in two constructions: as a plural noun (like earnings), taking a plural verb and plural modifiers (such as these, many, a few) but not cardinal numbers, and serving as a referent for plural pronouns (such as they, them); and as an abstract mass noun (like information), taking a singular verb and singular modifiers (such as this, much, little), and being referred to by a singular pronoun (it). Both constructions are standard. The plural construction is more common in print, evidently because the house style of several publishers mandates it.

Synonyms

• fact
• detail

Examples of datum in a Sentence

let's begin our discussion of this matter with a datum from actual experience

Recent Examples on the Web

The Story Continues This legal and ethical debate will likely persist, affecting the emerging data economy with a focus on data provenance, fair use, and transparent licensing. —Douglas B. Laney, Forbes.com, 29 June 2025

According to an analysis of Cook County data by Elevate, a nonprofit that studies energy efficiency, only about 30% of single-family homes in Chicago have central air conditioning, compared with 76% of homes nationwide. —Lily Carey, Chicago Tribune, 29 June 2025

In traditional robots, a control system analyzes sensory data and tells the machine what to do. —New Atlas, 29 June 2025

Indeed, according to the latest data reported by the International Air Transport Association (IATA)—which represents 350 airlines around the world—more than half (53 percent) of airplane accidents occur during landing. —Katie Jackson, Travel + Leisure, 29 June 2025

Word History

Etymology

Latin, from neuter of datus

First Known Use

1646, in the meaning defined at sense 1

Phrases Containing datum

• sense-datum

Rhymes for datum

• atom
• stratum
• erratum
• striatum
• substratum
• heteroatom
• petrolatum

Kids Definition

datum

noun

da·​tum ˈdāt-əm  ˈdat- 

ˈdät-

plural data -ə  or datums

: something used as a basis for reasoning or arriving at a conclusion or for calculating or measuring