English UsageComparison guide

Rollover vs. Roll Over

“Rollover” is the closed noun for a carried-forward prize or financial continuation/transfer. “Roll over” is the two-word phrasal verb, including physical movement and financial extension or transfer.

Quick answer

Use “rollover” as the noun in lottery, finance, and continuation contexts. Use “roll over” as the phrasal verb for turning over, yielding, or transferring/extending money, debt, or arrangements.

Key details

Confusion Familyword-boundary
Noun Variant ScopeThe noun is “rollover”; the phrasal verb is “roll over.”
Rule Familyorthographic-boundary
Termsrollover, roll over

Choose the right form

Decision table for Rollover vs. Roll Over
If you mean / needUseWhy
a carried-forward prize or financial event as a nounrolloverCambridge records the closed noun.
the action of turning, yielding, or extending/transferring an arrangementroll overCambridge records the phrasal verb as two words.

Further guidance

Core difference

Use the documented noun/adjective form for the thing, result, event, or modifier; use the spaced form when the expression functions as a verb or predicate.

Fast Test

Ask what job the expression is doing in the sentence. A noun/adjective form may be closed or hyphenated by dictionary convention; a verb or predicate normally keeps the words separate.

Variant Boundary

The noun is “rollover”; the phrasal verb is “roll over.”

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. Rollover — Cambridge Dictionary (opens in a new tab)Cambridge Dictionary · Closed noun “rollover” in prize, finance, and continuation contexts
  2. Roll over — Cambridge Dictionary (opens in a new tab)Cambridge Dictionary · Two-word phrasal verb “roll over” for bodily movement, yielding, or extending/transferring financial arrangements

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