tetrad

/ˈtɛtɹæd/

//ˈtɛtɹæd// noun

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

"tetrad" is a 6-letter English headword indexed on PlainSpell.

The verdict

“tetrad” is uncommon English (frequency #88,923 among 3,151 “T” headwords), classed as a noun. The kind of spelling people second-guess.

#88,923
frequency rank, English
3,151
“T” headwords

According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - A group of four things.

Corpus desk

Index EN-tetrad · tetrad · English

tetrad · rank #88,923 · 0 variants · 0 confusables

  • FREQ-RARE #88,923
  • LEN-LONG 6 letters
  • VOW-2 2 vowels
  • CONFUS-0 No pairs
  • VAR-0 0 variants
  • BOOK-MID 3,151
  • PHOTO-FINISH terrine

Nearest frequency peer: terrine (-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 “tetrad”

Sparse band: bars invert rank so rarer forms read shorter

corpus weight

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

Source FrequencyWords open word-frequency list As of September 3, 2026
Key facts for tetrad
PropertyValue
Headwordtetrad
LanguageEnglish
Part of speechNoun
IPA/ˈtɛtɹæd/
Letters6
Frequency rank#88,923
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Long-tail rank of “tetrad” in English

Word frequency stretches from the small set of words we reach for constantly (left) out to the long tail barely used once in a while (right).tetradfalls in this rarity band:

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

The axis is logarithmic, with each marked tick roughly ten times rarer than the last. Rare peers in the same band: “terrine” (#88,922), “thermostatic” (#88,925), “thickener” (#88,926). Among 3,151 “T” headwords, “tetrad” is #88,923. Source: FrequencyWords open word-frequency list.

Rare enough to double-check

tetrad is uncommon English at frequency #88,923 among 3,151 “T” headwords, classed as anoun, transcribed /ˈtɛtɹæd/. Rarity is why readers land here mid-draft. 7 senses are on record.

Zero misspellings are on record for tetrad in our index, and the word's spelling is regular enough that our generator found nothing worth flagging. No confusable counterpart is on file for this word, which typically means the spelling is too distinctive to be mistaken for another word.

Etymologically, the entry records: From Ancient Greek τετράς (tetrás), analysable as tetra- + -ad. The correct English form is tetrad, spelled T-E-T-R-A-D.

Definition

  1. 1
    A group of four things.
  2. 2
    Two pairs of sister chromatids (a dyad pair) aligned in a certain way and often on the equatorial plane during the meiosis process.
  3. 3
    A group of four haploid and immature pollen grains in tetrahedral fashion produced by meiotic microsporogenesis.
  4. 4
    A unit of land area of two by two (that is, four) square kilometres.
  5. 5
    A tetravalent atom or radical.
  6. 6
    A group of four basis vectors for a four-dimensional manifold in differential geometry.
  7. 7
    A chord comprised of four notes; a tetrachord.

Recorded use

Wiktionary examples

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

  1. Religious movements and cults are often founded on a tetrad of elements: a prophet, a prophecy, a book, and a revelation.
  2. They took figures for the abundance of invasive weeds mapped according to the normal grid unit of the 'hectad', or 10 × 10 km square, and then looked at how abundant these species were mapped at a much finer scale – in 'tetrads', or 2 × 2 km squares, inside these hectads.

Etymology

From Ancient Greek τετράς (tetrás), analysable as tetra- + -ad.

This word in other languages

tétrade(Français)Tetrade(Deutsch)

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 "tetrad"?
"tetrad" is spelled T-E-T-R-A-D. The IPA pronunciation is /ˈtɛtɹæd/.
What does "tetrad" mean?
As a noun, "tetrad" means: A group of four things.
How do you pronounce "tetrad"?
The IPA (International Phonetic Alphabet) transcription for "tetrad" is /ˈtɛtɹæd/. 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 "tetrad"?
From Ancient Greek τετράς (tetrás), analysable as tetra- + -ad. 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 "tetrad", not the corpus desk frequency band.

Same letter count

Frequency-ranked English headwords with 6 letters (nearest by frequency rank).

thwack#88,928Tralee#88,942stripy#88,891splish#88,883

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

Source: FrequencyWords open word-frequency list