English UsageComparison guide

Cleanup vs. Clean Up

“Cleanup” is a noun for an act or instance of cleaning and can also function adjectivally in established uses. “Clean up” is the verb phrase for making something clean or improving a situation.

Quick answer

Use “cleanup” for the noun (“the cleanup”) and “clean up” for the verb (“clean up the room”).

Key details

Confusion Familyword-boundary
Rule Familyorthographic-boundary
Termscleanup, clean up

Choose the right form

Decision table for Cleanup vs. Clean Up
If you mean / needUseWhy
the cleaning operation or result as a thingcleanupIt is the noun; some established attributive uses also use the closed form.
the action of making clean or improvingclean upIt is the verb.

Further guidance

Core difference

The one-word form names the cleanup; the two-word form performs the action.

Fast Test

If the phrase takes tense—“cleaned up,” “cleaning up”—use two words.

Modifier Boundary

Merriam-Webster also records adjectival “cleanup” in established uses, so not every closed form is strictly a noun.

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. Cleanup — Merriam-Webster (opens in a new tab)Merriam-Webster · Cleanup noun/adjective and clean up verb word-class boundary

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