datum

/ˈdeɪtəm/

//ˈdeɪtəm// noun

By · According to Wiktionary data (CC BY-SA) ·

"datum" is a 5-letter English headword indexed on PlainSpell.

The verdict

“datum” is uncommon English (frequency #51,645 among 3,470 “D” headwords), classed as a noun. The kind of spelling people second-guess.

#51,645
frequency rank, English
3,470
“D” headwords

According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - Something known or assumed as fact, and is made the basis of reasoning or inference which an intellectual system of any sort (such as knowledge or theoretical framework) is constructed.

Corpus desk

Index EN-datum · datum · English

datum · rank #51,645 · 0 variants · 0 confusables

  • FREQ-RARE #51,645
  • LEN-MID 5 letters
  • VOW-2 2 vowels
  • CONFUS-0 No pairs
  • VAR-0 0 variants
  • BOOK-MID 3,470
  • PHOTO-FINISH darshan

Nearest frequency peer: darshan (-1 rank slots)

Read with this headword: Spelling guide for this pattern

Desk codes from Wiktionary headword shape, FrequencyWords rank tier, confusable-pair count, generated misspelling depth, letter-cohort book size, and photo-finish peer. Not a difficulty grade.

Long-tail ranks near “datum”

Sparse band: bars invert rank so rarer forms read shorter

corpus weight

What this shows Long-tail view: where “datum” sits against similarly uncommon English ranks.

Source FrequencyWords open word-frequency list As of September 3, 2026
Key facts for datum
PropertyValue
Headworddatum
LanguageEnglish
Part of speechNoun
IPA/ˈdeɪtəm/
Letters5
Frequency rank#51,645
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Long-tail rank of “datum” in English

Every-word frequency runs from the handful of words we use constantly (left) to the long tail used once in a blue moon (right).datumfalls in this rarity band:

#1#100#1K#10K#100K
← used constantlyrarely used →

Scale is logarithmic (each tick is 10× rarer). Rare peers in the same band: “darshan” (#51,644), “deathmatch” (#51,648), “cutesy” (#51,641). Among 3,470 “D” headwords, “datum” is #51,645. Source: FrequencyWords open word-frequency list.

Rare enough to double-check

datum is uncommon English at frequency #51,645 among 3,470 “D” headwords, classed as anoun, transcribed /ˈdeɪtəm/. Rarity is why readers land here mid-draft. 4 senses are on record.

datum has no tracked misspelling variants, which points to an orthography that plays by predictable English rules. Our confusable-pair dataset has no match for it, since nothing in our dataset looks or sounds close enough to cause mix-ups.

Etymologically, the entry records: Borrowed from Latin datum (“a given”). Doublet of die. The correct English form is datum, spelled D-A-T-U-M.

Definition

  1. 1
    Something known or assumed as fact, and is made the basis of reasoning or inference which an intellectual system of any sort (such as knowledge or theoretical framework) is constructed.
  2. 2
    Singular of data: A single recorded phenomenon, especially obtained by scientific work.
  3. 3
    A point, line, plane, or surface with reference to which positions (such as elevations) are measured or indicated. (Examples include a permanent benchmark in leveling or mean sea level in a topographical survey).
  4. 4
    A floating reference point, or SLDMB, used to evaluate surface currents in a body of water, and often employed by coastal search and rescue.

Recorded use

Wiktionary examples

These source excerpts show how datum appears in context. They illustrate usage; the definition above remains the entry’s reference meaning.

  1. a datum of experience
  2. given this datum, it follows that

Etymology

Borrowed from Latin datum (“a given”). Doublet of die.

This word in other languages

dato(Español)donnée(Français)Fakt(Deutsch)dado(Português)

Definitions, pronunciation, and etymology for this entry are drawn from Wiktionary via the kaikki.org structured extract (CC BY-SA); frequency ordering uses the FrequencyWords open word-frequency list (2018 English corpus, MIT). See the methodology for how each field is sourced and updated.

Frequently Asked Questions

How do you spell "datum"?
"datum" is spelled D-A-T-U-M. The IPA pronunciation is /ˈdeɪtəm/.
What does "datum" mean?
As a noun, "datum" means: Something known or assumed as fact, and is made the basis of reasoning or inference which an intellectual system of any sort (such as knowledge or theoretical framework) is constructed.
How do you pronounce "datum"?
The IPA (International Phonetic Alphabet) transcription for "datum" is /ˈdeɪtəm/. Click the speaker icon on the pronunciation badge above to hear it spoken aloud where audio is available.
What is the origin of the word "datum"?
Borrowed from Latin datum (“a given”). Doublet of die. See the full etymology section above for more details.
Is PlainSpell free to use?
Yes, PlainSpell is a completely free word reference. You can look up definitions, pronunciations, confusable pairs, homophones, and spelling corrections across 5 languages without any sign-up or subscription.

Similar English words by spelling shape

Same letter count and similar misspelling depth for "datum", not the corpus desk frequency band.

Same letter count

Frequency-ranked English headwords with 5 letters (nearest by frequency rank).

creak#51,636crags#51,634Delos#51,656dinos#51,659

Source: Wiktionary (via kaikki.org) Structured Wiktionary extract

Source: FrequencyWords open word-frequency list