sacrum

/ˈsækɹəm/

//ˈsækɹəm// noun

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

The verdict

“sacrum” is uncommon English (frequency #63,219 among 6,566 “S” headwords), classed as a noun. The kind of spelling people second-guess.

#63,219
frequency rank, English
6,566
“S” headwords

According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - A large triangular bone at the base of the spine, located between the two ilia (wings of the pelvis) and formed from vertebrae that fuse in adulthood.

Corpus desk

Index EN-sacrum · sacrum · English

sacrum · rank #63,219 · 0 variants · 0 confusables

  • FREQ-RARE #63,219
  • LEN-LONG 6 letters
  • VOW-2 2 vowels
  • CONFUS-0 No pairs
  • VAR-0 0 variants
  • BOOK-DENSE 6,566
  • PHOTO-FINISH Sandys

Nearest frequency peer: Sandys (+2 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 “sacrum”

Sparse band: bars invert rank so rarer forms read shorter

corpus weight

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

Source FrequencyWords open word-frequency list As of September 3, 2026
Key facts for sacrum
PropertyValue
Headwordsacrum
LanguageEnglish
Part of speechNoun
IPA/ˈsækɹəm/
Letters6
Frequency rank#63,219
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Long-tail rank of “sacrum” 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).sacrumfalls 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: “Sandys” (#63,221), “rupiah” (#63,216), “Runcorn” (#63,215). Among 6,566 “S” headwords, “sacrum” is #63,219. Source: FrequencyWords open word-frequency list.

Rare enough to double-check

sacrum is uncommon English at frequency #63,219 among 6,566 “S” headwords, classed as anoun, transcribed /ˈsækɹəm/. Rarity is why readers land here mid-draft. Gloss: "A large triangular bone at the base of the spine, located between the two ilia (wings of the pelvis) and formed from vertebrae that fuse in adulthood.".

Zero misspellings are on record for sacrum in our index, since its letter sequence doesn't invite the usual edit-distance slips. It is not paired with a close-neighbour confusable in our dataset, a sign it's visually distinctive enough not to be mixed up with another word.

Etymologically, the entry records: From Latin os sacrum (“holy bone”), a calque of Ancient Greek ἱερὸν ὀστέον (hieròn ostéon). Apparently so called either because the sacrum was the part of the animal offered in sacrifice or because of a putative belief that it is where a person's soul resid… The correct English form is sacrum, spelled S-A-C-R-U-M.

Definition

  1. 1
    A large triangular bone at the base of the spine, located between the two ilia (wings of the pelvis) and formed from vertebrae that fuse in adulthood.

Etymology

From Latin os sacrum (“holy bone”), a calque of Ancient Greek ἱερὸν ὀστέον (hieròn ostéon). Apparently so called either because the sacrum was the part of the animal offered in sacrifice or because of a putative belief that it is where a person's soul resides. A third explanation is that the term is a translation of Ancient Greek ἱερόν (hierón), which has two meanings: “holy, sacred”, and “big” — big being a more appropriate description of the sacrum — but compare.

This word in other languages

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 "sacrum"?
"sacrum" is spelled S-A-C-R-U-M. The IPA pronunciation is /ˈsækɹəm/.
What does "sacrum" mean?
As a noun, "sacrum" means: A large triangular bone at the base of the spine, located between the two ilia (wings of the pelvis) and formed from vertebrae that fuse in adulthood.
How do you pronounce "sacrum"?
The IPA (International Phonetic Alphabet) transcription for "sacrum" is /ˈsækɹəm/. 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 "sacrum"?
From Latin os sacrum (“holy bone”), a calque of Ancient Greek ἱερὸν ὀστέον (hieròn ostéon). Apparently so called either because the sacrum was the part of the animal offered in sacrifice or because of a putative belief that it is where a person's ... 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 "sacrum", not the corpus desk frequency band.

Same letter count

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

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

Source: FrequencyWords open word-frequency list