out break (outbreak)

Writers sometimes split the compound outbreak into two words ("out break") or insert a hyphen ("out-break"). That spacing or hyphenation error looks small but can confuse readers and make writing look unpolished.

Quick answer

Write outbreak as one word for the noun meaning a sudden occurrence or increase. Use break out (two words) when you need a verb phrase: something breaks out.

Wrong: There was an out break of flu in the dorms. (incorrect spacing)
Right: There was an outbreak of flu in the dorms. (correct noun)
Verb form: Violence broke out after the rally. (use break out as a verb)

Core explanation: outbreak is one word

Outbreak is a closed compound noun that names a sudden start or sharp increase-disease, violence, protests, laughter, and similar events. It follows the pattern of many out- compounds that have become single words.

Outbreak (noun) = a sudden start or surge
Break out (verb) = an action that begins suddenly

Wrong: There was an out break of the flu in the office.
Right: There was an outbreak of the flu in the office.
Example: An outbreak of protests swept the city.

Spacing and hyphenation: don't split or hyphenate

Modern usage treats outbreak as a single word. Writing out break or out-break is a spacing or hyphenation error unless you actually mean the verb phrase break out.

Don't write: out break or out-break - write outbreak.
Hyphens sometimes appear in older texts or nonstandard uses, but outbreak does not need one.

Wrong: There was an out-break of the disease last winter.
Right: There was an outbreak of the disease last winter.

Grammar: noun vs verb - outbreak vs break out

Choose the noun when referring to the event itself: "an outbreak of X." Choose the verb when describing something beginning: "X broke out."

Noun: an outbreak of measles
Verb: Measles broke out

Wrong: There was an break out of riots last night.
Right: There was an outbreak of riots last night.
Verb option: Riots broke out last night.

Examples you can copy: work, school, casual

Below are wrong/correct pairs for professional, academic, and casual contexts. Copy the correct sentence or use the rewrite patterns shown.

Work - Wrong: There was an out break of malware across employee laptops.
Work - Right: There was an outbreak of malware across employees' laptops.
Work - Wrong: There was an out break of customer complaints after the update.
Work - Right: There was an outbreak of customer complaints after the update.
Work - Wrong: There was an out break of absenteeism in the sales team.
Work - Right: There was an outbreak of absenteeism in the sales team.
School - Wrong: There was an out break of flu in the dorms.
School - Right: There was an outbreak of flu in the dorms.
School - Wrong: There was an out break of cheating during finals.
School - Right: There was an outbreak of cheating during finals.
School - Wrong: There was an out break of protests after the campus decision.
School - Right: There was an outbreak of protests after the campus decision.
Casual - Wrong: There was an out break of laughter when he told the story.
Casual - Right: There was an outbreak of laughter when he told the story.
Casual - Wrong: There was an out break of mosquitoes by the campsite.
Casual - Right: There was an outbreak of mosquitoes by the campsite.
Casual - Wrong: There was an out break of spoilers after the premiere.
Casual - Right: There was an outbreak of spoilers after the premiere.
Rewrite option: Instead of "There was an outbreak of flu in the office," write "Flu cases broke out in the office."
Rewrite option: Instead of "There was an outbreak of protests," write "Protests broke out across the city."
Rewrite option: Instead of "There was an outbreak of complaints," write "Complaints began to surge after the update."

Try your own sentence

Test the whole sentence - context usually makes the right form obvious. Paste your sentence into the checker below to flag spacing and hyphenation issues.

How to fix your own sentence (step-by-step)

Follow these quick steps: identify the phrase, decide noun vs verb, fix spacing and hyphens, and use a rewrite if the sentence feels awkward.

Templates to copy:

Noun: "There was an outbreak of [problem/illness]."
Verb: "[Problem] broke out in [place/when]."

Checklist: Is it naming an event? → outbreak. Is it describing an action? → break out.
Example - Wrong: There was an out break of software glitches during launch.
Example - Right (noun): There was an outbreak of software glitches during the launch.
Example - Rewrite (verb): Software glitches broke out during the launch.

Real usage and tone: where outbreak sounds natural

Outbreak fits formal and neutral writing-reports, research, and news-especially for serious topics like disease, violence, or protests. The verb phrase break out works better for a punchier, conversational tone.

Formal/neutral: There was an outbreak of food poisoning at the restaurant.
News or active lead: Violence broke out after the decision was announced.
Casual: Spoilers broke out online right after the episode aired.

Memory tricks and quick checks

Trick 1: Read the phrase aloud. If you naturally say "There was an ..." before it, use outbreak. If you say "... broke out," use the verb form.

Trick 2: Substitute a synonym. If "sudden surge" fits, choose outbreak. If "began suddenly" fits, choose break out.

If you can put "an" before it, prefer outbreak.
If the sentence needs an active verb, use break out.

Similar mistakes to watch for

Other out- compounds often close up: outcome (not out come), outset (not out set), outlaw (not out law). Apply the same quick check: would "an" fit? Is the phrase naming an event?

Also note breakout (one word) exists with different senses: a breakout hit or a breakout session. Don't confuse breakout with outbreak.

Outcome - not "out come"
Break out (verb) vs breakout (single word for sudden success/event)
Outset - not "out set"

Wrong: The concert was a break out hit this summer.
Right: The concert was a breakout hit this summer.

FAQ

Is "outbreak" one word or two?

Outbreak is one word when used as a noun to mean a sudden occurrence or increase. Writing it as out break is a spacing error.

Can I write "out-break" with a hyphen?

No. Modern usage favors the closed form outbreak. A hyphenated out-break looks nonstandard; change it to outbreak unless a specific style guide or historical text requires the hyphen.

When should I use "break out" instead of "outbreak"?

Use break out (two words) when you need a verb: "Fights broke out" or "A rash broke out on his arm." Use outbreak as a noun: "an outbreak of fights" or "an outbreak of rash cases."

Is "outbreak of laughter" correct?

Yes. Outbreak of laughter describes a sudden, collective start of laughter. You can also say "laughter broke out" for a more active tone.

How do I correct "There was an out break of X" quickly?

Change it to "There was an outbreak of X." If you prefer active wording, rewrite as "X broke out" or "Cases of X began to appear." A simple noun-vs-verb checklist prevents most errors.

Want to check a sentence now?

If you're unsure about a compound or the noun/verb choice, paste your sentence into the checker above. It flags spacing and hyphenation errors and suggests rewrites you can use immediately.