English UsageComparison guide

Sellout vs. Sell Out

“Sellout” is a closed noun and adjective in Cambridge’s main dictionary, while Business English also documents “sell-out” as a noun variant. “Sell out” is the two-word phrasal verb.

Quick answer

Use “sellout” as the closed noun in Cambridge’s main entry, for example an event with all tickets sold or a perceived betrayal of principles. Cambridge Business English also records the hyphenated noun “sell-out.” Use “sell out” as the phrasal verb.

Key details

Confusion Familyword-boundary
Noun Variant ScopeCambridge records closed “sellout” as a noun/adjective and also documents hyphenated “sell-out” as a Business English noun; the phrasal verb is “sell out.”
Rule Familyorthographic-boundary
Termssellout, sell-out, sell out

Choose the right form

Decision table for Sellout vs. Sell Out
If you mean / needUseWhy
a sold-out event or a betrayal as a nounselloutCambridge records the closed noun.
a Business English noun variantsell-outCambridge documents the hyphenated noun variant.
the action of selling all stock, a business, or principlessell 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 closed “sellout” as a noun/adjective and also documents hyphenated “sell-out” as a Business English noun; the phrasal verb is “sell out.”

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. SELLOUT — English meaning (opens in a new tab)Cambridge Dictionary · Closed noun/adjective “sellout”
  2. SELL OUT — English meaning (opens in a new tab)Cambridge Dictionary · Two-word phrasal verb and documented Business English noun variant “sell-out”

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