ilium

/ˈɪlɪəm/

//ˈɪlɪəm// noun

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

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

The verdict

“ilium” is uncommon English (frequency #72,415 among 2,140 “I” headwords), classed as a noun. The kind of spelling people second-guess.

#72,415
frequency rank, English
2,140
“I” headwords

According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - The upper and widest of the three bones that make up each side of the hipbone.

Corpus desk

Index EN-ilium · ilium · English

ilium · rank #72,415 · 0 variants · 0 confusables

  • FREQ-RARE #72,415
  • LEN-MID 5 letters
  • VOW-3 3 vowels
  • CONFUS-0 No pairs
  • VAR-0 0 variants
  • BOOK-MID 2,140
  • PHOTO-FINISH impaling

Nearest frequency peer: impaling (+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 “ilium”

Sparse band: bars invert rank so rarer forms read shorter

corpus weight

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

Source FrequencyWords open word-frequency list As of September 3, 2026
Key facts for ilium
PropertyValue
Headwordilium
LanguageEnglish
Part of speechNoun
IPA/ˈɪlɪəm/
Letters5
Frequency rank#72,415
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Long-tail rank of “ilium” 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).iliumfalls in this rarity band:

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

Ticks step logarithmically, so each one marks a roughly tenfold drop in how often the word turns up. Rare peers in the same band: “impaling” (#72,416), “ignorantly” (#72,412), “incomparably” (#72,419). Among 2,140 “I” headwords, “ilium” is #72,415. Source: FrequencyWords open word-frequency list.

Rare enough to double-check

ilium is uncommon English at frequency #72,415 among 2,140 “I” headwords, classed as anoun, transcribed /ˈɪlɪəm/. Rarity is why readers land here mid-draft. 2 senses are on record.

We couldn't generate a plausible misspelling set for ilium, typically a sign the spelling maps closely to how the word sounds. We don't track a confusable pairing for this entry, which typically means the spelling is too distinctive to be mistaken for another word.

Etymologically, the entry records: Borrowed from Latin īlium (“lower abdomen”), from īle (“flank”). The correct English form is ilium, spelled I-L-I-U-M.

Definition

  1. 1
    The upper and widest of the three bones that make up each side of the hipbone.
  2. 2
    The ileum, part of the small intestine (in modern usage, misspelling of ileum).

Recorded use

Wiktionary example

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

  1. Holonyms: hip bone, os coxae < pelvis

Etymology

Borrowed from Latin īlium (“lower abdomen”), from īle (“flank”).

This word in other languages

ilion(Español)

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 "ilium"?
"ilium" is spelled I-L-I-U-M. The IPA pronunciation is /ˈɪlɪəm/.
What does "ilium" mean?
As a noun, "ilium" means: The upper and widest of the three bones that make up each side of the hipbone.
How do you pronounce "ilium"?
The IPA (International Phonetic Alphabet) transcription for "ilium" is /ˈɪlɪəm/. 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 "ilium"?
Borrowed from Latin īlium (“lower abdomen”), from īle (“flank”). 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 "ilium", not the corpus desk frequency band.

Same letter count

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

Jalil#72,441Kadir#72,453kavya#72,457gored#72,356

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

Source: FrequencyWords open word-frequency list