English Word Reference Free

running-in

Definition, pronunciation, etymology, and usage for the English word. Free spelling reference powered by Wiktionary.

Detailed reference entry for the English word "running-in", 10-letters, with pronunciation in International Phonetic Alphabet notation, etymology traced through Germanic and Romance roots where applicable, common misspelling variants catalogued from Wiktionary, and usage frequency ranked against an open word-frequency list covering the top 100,000 English words. PlainSpell covers English, Spanish, Portuguese, French, and German spelling with confusable-pair detection that highlights visually and phonetically similar words. This entry for "running-in" includes synonyms, antonyms, homophones, and cross-language translation pointers sourced from Wiktionary via the kaikki.org extract. Whether you are verifying the correct spelling of "running-in" for academic writing, checking homophone confusion, or exploring etymological origins, this page provides a citation-backed, free reference that requires no sign-up.

The verdict

“running in” is outside the top-ranked English vocabulary, used as a noun - the kind of word writers most often double-check.

Unranked
below top-frequency English
10
letters

Dominant Wiktionary sense: The operating of a new engine (especially that of a motor vehicle) at less than its normal speed until proper working has been established.

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Key facts for running in
PropertyValue
Headwordrunning in
LanguageEnglish
Part of speechNoun
Letters10
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Where “running in” sits in English frequency

running in falls outside the top-100,000 ranked English words, the long-tail zone of technical, archaic, or low-frequency vocabulary, exactly where readers second-guess spellings most.

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

Spelling & Dictionary Insight

The English entry for running in is 10 letters long, classified as a noun. It sits outside the most-frequent rank tiers, which is often why uncommon words generate more spelling variants per reader. The dominant gloss from Wiktionary reads: "The operating of a new engine (especially that of a motor vehicle) at less than its normal speed until proper working has been established.".

No misspelling variants are generated for running in in our index, suggesting the orthography follows predictable English patterns. It is not paired with a close-neighbour confusable in our dataset, which tends to mean the word is visually distinctive enough to stand on its own.

No explicit etymology string is stored for this entry, so spelling patterns must be inferred from the word's phoneme-to-grapheme mapping rather than from a documented borrowing chain. For readers arriving here from a spelling check, the authoritative guidance is: the correct English form is running in, spelled R-U-N-N-I-N-G- -I-N, and any other sequence of those letters, regardless of how natural it feels, is a misspelling in standard orthography.

Definition

  1. 1
    The operating of a new engine (especially that of a motor vehicle) at less than its normal speed until proper working has been established.

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.

Cite this page

Free to reuse with attribution (CC BY-SA). Copy the citation:

PlainSpell, “running in, English word data” (May 6, 2026). Derived from Wiktionary (kaikki.org, CC BY-SA) and an open word-frequency list. https://plainspell.com/en/word/running-in

Frequently Asked Questions

How do you spell "running in"?
"running in" is spelled R-U-N-N-I-N-G- -I-N.
What does "running in" mean?
As a noun, "running in" means: The operating of a new engine (especially that of a motor vehicle) at less than its normal speed until proper working has been established.
What language does "running in" come from?
"running in" is a English word. PlainSpell covers definitions, pronunciations, and spelling data across English, Spanish, Portuguese, French, and German.
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 “running in”

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

  • The one correct English spelling is R-U-N-N-I-N-G- -I-N - every other letter order is a misspelling in standard orthography.
  • Browse more English words and confusable pairs in the same reference. English words

Nearby English words

Other entries that begin with the letter R in our English index:

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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