light up

verb

"light-up" is a 7-letter English headword indexed on PlainSpell.

The verdict

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

Unranked
below top-frequency English
8
letters

According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - To illuminate, to bring light to something, to brighten.

Corpus desk

Index EN-light-up · light up · English

light up · unranked · 0 variants · 0 confusables

  • FREQ-UNRANKED Unranked
  • LEN-LONG 8 letters
  • VOW-2 2 vowels
  • CONFUS-0 No pairs
  • VAR-0 0 variants
  • BOOK-THIN "L" 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 light up
PropertyValue
Headwordlight up
LanguageEnglish
Part of speechVerb
Letters8
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Long-tail rank of “light up” in English

light upsits 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

light up is uncommon English outside the top frequency list, classed as averb. Rarity is why readers land here mid-draft. 11 senses are on record.

No generated misspelling entries exist for light up in our index, which points to an orthography that plays by predictable English rules. Our confusable-pair dataset has no match for it, which usually means its spelling is distinct enough that readers don't reach for a similar-looking word instead.

Etymologically, the entry records: Phrasal verb from light (“to make bright, ignite”, verb) + up (“to a higher degree”, adverb). The correct English form is light up, spelled L-I-G-H-T- -U-P.

Definition

  1. 1
    To illuminate, to bring light to something, to brighten.
  2. 2
    To start to emit light; to become activated as a light source.
  3. 3
    To show an increase in activity or a brightening of mood.
  4. 4
    To ignite.
  5. 5
    To light a cigarette, pipe, etc.
  6. 6
    To light a cigarette, pipe, etc. for (someone).
  7. 7
    To make happy.
  8. 8
    To introduce (someone to something), to make someone aware of or interested in something; turn on.
  9. 9
    To open fire on a target or group of targets, especially with rockets, a flamethrower, etc.
  10. 10
    To shock (someone) with a stun gun.
  11. 11
    To activate the emergency sirens on a police vehicle in order to pull someone over.

Recorded use

Wiktionary examples

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

  1. The deafening claps of thunder and the dazzling flashes of lightning which lit up the ghastly scene testified that the artillery of heaven had lent its supernatural pomp to the already gruesome spectacle.
  2. I've never seen a supernova blow up, but if it's anything like my old Chevy Nova, it'll light up the night sky.

Etymology

Phrasal verb from light (“to make bright, ignite”, verb) + up (“to a higher degree”, adverb).

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 "light up"?
"light up" is spelled L-I-G-H-T- -U-P.
What does "light up" mean?
As a verb, "light up" means: To illuminate, to bring light to something, to brighten.
What is the origin of the word "light up"?
Phrasal verb from light (“to make bright, ignite”, verb) + up (“to a higher degree”, adverb). 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