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speed-of-light

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

Letters

14 characters

Language

English

word origin

Source

Wiktionary

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Detailed reference entry for the English word "speed-of-light", 14-letters, with pronunciation in International Phonetic Alphabet notation, etymology traced through Germanic and Romance roots where applicable, common misspelling variants catalogued from Hunspell error dictionaries, and usage frequency ranked against the top 100,000 English words in the Wordfreq corpus. PlainSpell covers English, Spanish, Portuguese, French, and German spelling with confusable-pair detection that highlights visually and phonetically similar words. This entry for "speed-of-light" 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 "speed-of-light" for academic writing, checking homophone confusion, or exploring etymological origins, this page provides a citation-backed, free reference that requires no sign-up.

speed of light is aEnglishnoun. It means: The speed of electromagnetic radiation, which in a perfect vacuum is equivalent to 299,792,458 metres per second.

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Key facts for speed of light
PropertyValue
Headwordspeed of light
LanguageEnglish
Part of speechNoun
Letters14
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Frequency rank visualization

speed of light is not present in the top-100,000 ranked English corpus, typical for technical, archaic, or low-frequency vocabulary.

Source: Wordfreq corpus

Spelling & Dictionary Insight

The English entry for speed of light is 14 letters long, classified as anoun. It sits outside the most-frequent rank tiers, which is often why uncommon words generate more spelling variants per reader.Wiktionary records 3 distinct senses for this headword, so context determines which meaning a reader should apply.

No frequent misspelling variants are recorded for speed of light in our index, suggesting the orthography either follows predictable English patterns or the word is uncommon enough that typo corpora lack signal.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 speed of light, spelled S-P-E-E-D- -O-F- -L-I-G-H-T, and any other sequence of those letters, regardless of how natural it feels, is a misspelling in standard orthography.

Definition

  1. 1
    The speed of electromagnetic radiation, which in a perfect vacuum is equivalent to 299,792,458 metres per second.
  2. 2
    A very rapid speed.
  3. 3
    A rate of travel of a signal equal to one cell per generation, the fastest possible speed in the Moore and von Neumann neighborhoods.

This word in other languages

Frequently Asked Questions

How do you spell "speed of light"?
"speed of light" is spelled S-P-E-E-D- -O-F- -L-I-G-H-T.
What does "speed of light" mean?
As a noun, "speed of light" means: The speed of electromagnetic radiation, which in a perfect vacuum is equivalent to 299,792,458 metres per second.
What language does "speed of light" come from?
"speed of light" 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.

Nearby English words

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

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Data Source: Wiktionary (via kaikki.org), licensed under CC BY-SA & GFDL. Frequency data from Wordfreq. Misspellings derived from Hunspell dictionaries.