# datum

Pronunciation: say "DAY-tuhm" /ˈdeɪtəm/

## Noun

1. Singular of data. — Singular of data: A single recorded material, especially obtained by scientific work.
   - Simple: Singular of data. Use this form when you mean just one piece of information.
   - _Each datum was recorded by hand in the laboratory notebook._
   - _A single datum on its own rarely tells the whole story._
2. A fixed point, line, or surface used as a reference from which positions or elevations are measured.
   - Simple: A fixed point or line that you measure other positions from.
   - _Surveyors established a permanent datum before mapping the valley's elevations._
   - _All heights on the chart are measured from a single tidal datum._

## Other meanings

- (noun) In search and rescue, the estimated position of a person or object in the water, worked out from the last known position corrected for drift.
- (verb) To adjust measurements, especially seismic data, so that they appear to have been recorded at a chosen reference level or surface.

## Origin

English took the word directly from Latin datum, meaning "a given." Die is a doublet.

Source: DictionaryAI, https://dictionaryai.com/define/datum (written from Wiktionary data, CC BY-SA 4.0: https://creativecommons.org/licenses/by-sa/4.0/).