undulation

noun

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

The verdict

“undulation” is uncommon English (outside the top frequency list), classed as a noun. The kind of spelling people second-guess.

Unranked
below top-frequency English
10
letters

According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - An instance or act of undulating.

Corpus desk

Index EN-undulation · undulation · English

undulation · unranked · 0 variants · 0 confusables

  • FREQ-UNRANKED Unranked
  • LEN-MEGA 10 letters
  • VOW-5 5 vowels
  • CONFUS-0 No pairs
  • VAR-0 0 variants
  • BOOK-THIN "U" thin
  • PHOTO-UNK Peer pending

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.

Key facts for undulation
PropertyValue
Headwordundulation
LanguageEnglish
Part of speechNoun
Letters10
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Long-tail rank of “undulation” in English

undulationsits beyond the 100,000 most-frequent English words, in the long tail of technical, archaic, or otherwise rare vocabulary where spelling doubt tends to strike hardest.

Beyond rank #100,000. Source: FrequencyWords open word-frequency list.

Rare enough to double-check

undulation is uncommon English outside the top frequency list, classed as anoun. Rarity is why readers land here mid-draft. 7 senses are on record.

Our edit-distance generator produced no likely misspellings for undulation, and the word's spelling is regular enough that our generator found nothing worth flagging. No close-neighbour confusable shows up for this headword in our dataset, suggesting its spelling stands apart enough that readers rarely confuse it with something else.

Etymologically, the entry records: From undulate + -ion, or borrowed from Medieval Latin undulātiō; compare French ondulation. The correct English form is undulation, spelled U-N-D-U-L-A-T-I-O-N.

Definition

  1. 1
    An instance or act of undulating.
  2. 2
    A wavy appearance or outline; waviness.
  3. 3
    A tremulous tone produced by a peculiar pressure of the finger on a string.
  4. 4
    A wavelike curve; a smooth and regular rise and fall.
  5. 5
    A wavelike motion of the air; electromagnetic radiation.
  6. 6
    A feeling as if of an undulatory motion about the heart.
  7. 7
    The distinctive motion of the matter within an abscess on being pressed when it is ripe for opening.

Recorded use

Wiktionary example

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

  1. But the next undulation would raise us, showing the island ablaze in the sunlight, an emerald of dazzling beauty resting lightly on the bosom of the sea.

Etymology

From undulate + -ion, or borrowed from Medieval Latin undulātiō; compare French ondulation.

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). See the methodology for how each field is sourced and updated.

Frequently Asked Questions

How do you spell "undulation"?
"undulation" is spelled U-N-D-U-L-A-T-I-O-N.
What does "undulation" mean?
As a noun, "undulation" means: An instance or act of undulating.
What is the origin of the word "undulation"?
From undulate + -ion, or borrowed from Medieval Latin undulātiō; compare French ondulation. 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.

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

Source: FrequencyWords open word-frequency list