retardation

/ˌɹiː.tɑːˈdeɪ̯.ʃən/

//ˌɹiː.tɑːˈdeɪ̯.ʃən// noun

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

"retardation" is a 11-letter English headword indexed on PlainSpell.

The verdict

“retardation” is a moderately-common English word, ranked #33,395 in English word frequency and used as a noun.

#33,395
frequency rank, English
11
letters
17
tracked misspellings
2
confusable pairs

According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - The act of retarding or delaying; hindrance.

Visual similarity to commonly confused words

How many letter changes separate each confused pair (Levenshtein distance, normalized).

retardation vs reparation
82% similar
retardation vs retaliation
82% similar

Source: PlainSpell confusable corpus (Wiktionary, CC BY-SA).

Key facts for retardation
PropertyValue
Headwordretardation
LanguageEnglish
Part of speechNoun
IPA/ˌɹiː.tɑːˈdeɪ̯.ʃən/
Letters11
Frequency rank#33,395
Misspellings tracked17
Confusable pairs2
SourceWiktionary (kaikki.org)

Where “retardation” 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). retardation lands here:

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

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

Spelling & Dictionary Insight

The English entry for retardation is 11 letters long, classified as a noun, and transcribed in the International Phonetic Alphabet as /ˌɹiː.tɑːˈdeɪ̯.ʃən/. Corpus data places it at rank #33,395 in overall English word frequency, marking it as uncommon enough that many writers pause before typing it. Wiktionary records 9 distinct senses for this headword, so context determines which meaning a reader should apply.

Our generated misspelling index lists 17 likely wrong-spelling variants for retardation, with forms such as "ertardation", "reatrdation", and "retadration". Each of these forms differs from the correct spelling by one small edit: a doubled letter, a dropped silent letter, or a substituted vowel. It also participates in 2 confusable-pair relationships, "reparation", "retaliation", where similar look or sound leads writers to substitute one word for another in context.

Etymologically, the entry records: From retard + -ation. The correct English form is retardation, spelled R-E-T-A-R-D-A-T-I-O-N.

Definition

  1. 1
    The act of retarding or delaying; hindrance.
  2. 2
    The act of retarding or delaying; hindrance.
  3. 3
    The act of retarding or delaying; hindrance.
  4. 4
    The extent to which anything is retarded; the result of any retarding or delay; mental, social, or physical slowness.
  5. 5
    Ellipsis of mental retardation.
  6. 6
    Extreme stupidity.
  7. 7
    That which retards; an obstacle; an obstruction.
  8. 8
    Deceleration; reduction in the magnitude of velocity.
  9. 9
    A suspension which resolves upwards.

Etymology

From retard + -ation.

Common misspellings

Also misspelled as: ertardation,reatrdation,retadration,retaradtion,retardaiton,retardasion,retardatino,retardationn,retardatoin,retardattion,retarddation,retardtaion,retarrdation,retradation,rettardation,rretardation,rteardation

Misspelling Pattern Breakdown

How far each generated variant is from the correct spelling of retardation - measured in single-character edits (insert, delete, or substitute a letter). Larger bars are easier to catch; one-edit slips are the sneakiest.

ertardation2reatrdation2retadration2retaradtion2retardaiton2retardasion1retardatino2retardationn1
Edit distance from "retardation"

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 "retardation"?
"retardation" is spelled R-E-T-A-R-D-A-T-I-O-N. The IPA pronunciation is /ˌɹiː.tɑːˈdeɪ̯.ʃən/.
What does "retardation" mean?
As a noun, "retardation" means: The act of retarding or delaying; hindrance.
What words are commonly confused with "retardation"?
"retardation" is commonly confused with "reparation", "retaliation". These words look or sound similar but have different meanings. PlainSpell provides detailed comparisons for each pair.
How do you pronounce "retardation"?
The IPA (International Phonetic Alphabet) transcription for "retardation" is /ˌɹiː.tɑːˈdeɪ̯.ʃən/. 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 "retardation"?
From retard + -ation. 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 “retardation”

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

  • The one correct English spelling is R-E-T-A-R-D-A-T-I-O-N - every other letter order is a misspelling in standard orthography.
  • Say it as /ˌɹiː.tɑːˈdeɪ̯.ʃən/ (IPA); tap the speaker on the pronunciation badge to hear it where audio exists.
  • Don't mix it up with “reparation” - see the side-by-side comparison. retardation vs reparation
  • Browse more English words and confusable pairs in the same reference. English words
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 FrequencyWords open word-frequency list