English UsageComparison guide

Blowout vs. Blow Out

“Blowout” is a closed noun for several events or results, and Cambridge also records “blow-out” as a noun variant. “Blow out” is the two-word phrasal verb, including the sense of extinguishing a flame.

Quick answer

Use “blowout” for the noun in common modern uses; Cambridge also documents the hyphenated noun variant “blow-out.” Use “blow out” as the phrasal verb, such as extinguishing a flame.

Key details

Confusion Familyword-boundary
Noun Variant ScopeCambridge records “blowout” and also “blow-out” as noun forms; “blow out” is the phrasal verb.
Rule Familyorthographic-boundary
Termsblowout, blow-out, blow out

Choose the right form

Decision table for Blowout vs. Blow Out
If you mean / needUseWhy
a tyre burst, large meal/party, hairstyle, or lopsided result as a nounblowout / blow-outCambridge documents the closed noun and also the hyphenated noun variant.
the verb action, such as extinguishing a candleblow outCambridge records the phrasal verb as two words.

Further guidance

Core difference

Use the documented noun or modifier form when naming a thing, result, event, or concept; use the spaced form when the words function as a verb.

Fast Test

If the expression can take ordinary verb tense or inflection in the sentence, the spaced verb form is usually the relevant choice.

Variant Boundary

Cambridge records “blowout” and also “blow-out” as noun forms; “blow out” is the phrasal verb.

Sources and evidence

Sources are shown with the role they play in this guide. Historical or style-sensitive claims are kept within the evidence boundary described above.

  1. Blowout — Cambridge Dictionary (opens in a new tab)Cambridge Dictionary · Closed noun “blowout” plus documented hyphenated noun variant “blow-out”
  2. Blow out — Cambridge Dictionary (opens in a new tab)Cambridge Dictionary · Two-word phrasal verb “blow out” for extinguishing a flame and related verb uses

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