sacroiliac

/ˌsækɹoʊˈɪliˌæk/

//ˌsækɹoʊˈɪliˌæk// adj

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

"sacroiliac" is a 10-letter English headword indexed on PlainSpell.

The verdict

“sacroiliac” is uncommon English (frequency #97,517 among 54,294 “S” headwords), classed as an adjective. The kind of spelling people second-guess.

#97,517
frequency rank, English
54,294
“S” headwords

According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - Relating to the sacrum and ilium, or to the region of the lower back where they are located.

Key facts for sacroiliac
PropertyValue
Headwordsacroiliac
LanguageEnglish
Part of speechAdjective
IPA/ˌsækɹoʊˈɪliˌæk/
Letters10
Frequency rank#97,517
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Where “sacroiliac” sits in English frequency

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

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

Scale is logarithmic (each tick is 10× rarer). Source: FrequencyWords open word-frequency list.

Rare enough to double-check

sacroiliac is uncommon English at frequency #97,517 among 54,294 “S” headwords, classed as anadjective, transcribed /ˌsækɹoʊˈɪliˌæk/. Rarity is why readers land here mid-draft. Gloss: "Relating to the sacrum and ilium, or to the region of the lower back where they are located.".

Our edit-distance generator produced no likely misspellings for sacroiliac, a straightforward case of a spelling with little room for common typos. It is not paired with a close-neighbour confusable in our dataset, since nothing in our dataset looks or sounds close enough to cause mix-ups.

Etymologically, the entry records: From sacro- + iliac. The correct English form is sacroiliac, spelled S-A-C-R-O-I-L-I-A-C.

Definition

  1. 1
    Relating to the sacrum and ilium, or to the region of the lower back where they are located.

Etymology

From sacro- + iliac.

Synonyms

iliosacral

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 "sacroiliac"?
"sacroiliac" is spelled S-A-C-R-O-I-L-I-A-C. The IPA pronunciation is /ˌsækɹoʊˈɪliˌæk/.
What does "sacroiliac" mean?
As an adjective, "sacroiliac" means: Relating to the sacrum and ilium, or to the region of the lower back where they are located.
How do you pronounce "sacroiliac"?
The IPA (International Phonetic Alphabet) transcription for "sacroiliac" is /ˌsækɹoʊˈɪliˌæk/. 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 "sacroiliac"?
From sacro- + iliac. 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.

Using “sacroiliac”

The practical upshot for anyone who landed here from a spell-check.

  • The one correct English spelling is S-A-C-R-O-I-L-I-A-C - every other letter order is a misspelling in standard orthography.
  • Say it as /ˌsækɹoʊˈɪliˌæk/ (IPA); tap the speaker on the pronunciation badge to hear it where audio exists.
  • Browse more English words and confusable pairs in the same reference. English words

Other uncommon English words near this rank

Data Source

Wiktionary (via kaikki.org), licensed under CC BY-SA & GFDL. Word ordering uses an open word-frequency list; misspelling variants are generated by edit-distance from the correct headword.

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

Source: FrequencyWords open word-frequency list