“Write-off” is a hyphenated noun used for losses, deductions, or things treated as no longer useful or repairable. “Write off” is the two-word phrasal verb for the corresponding actions.
ReviewedEvidence1 sourceSectionEnglish Usage
Quick answer
Use “write-off” for the noun, such as an accounting loss or something judged beyond value or repair. Use “write off” as the verb.
Key details
Confusion Familyword-boundary
Noun Variant ScopeCambridge distinguishes the hyphenated noun “write-off” from the two-word phrasal verb “write off.”
Rule Familyorthographic-boundary
Termswrite-off, write off
Choose the right form
Decision table for Write-off vs. Write Off
If you mean / need
Use
Why
a noun for a loss, deduction, or unusable item
write-off
Cambridge records the noun with a hyphen.
the action of recording a loss or dismissing something as not useful
write off
The phrasal verb is written as two words.
Further guidance
Core difference
Use the documented noun or modifier form when naming a thing, result, person, 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 distinguishes the hyphenated noun “write-off” from the two-word phrasal verb “write off.”
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.
Standard English writes “a lot” as two words for a large amount, number, frequency, or degree. “Alot” is a common misspelling in this sense; it should not be confused with the separate verb “allot.”
“Blackout” is the closed noun, while “black out” is the two-word phrasal verb. The verb can describe losing consciousness or obscuring/darkening something; the noun names the resulting event or state.
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