law suit (lawsuit)

Short answer: Write "lawsuit" as one word when you mean a legal action. "Law suit" and "law-suit" are incorrect in modern usage.

Quick answer

"Lawsuit" is one closed compound. Use "sue" for the verb and "file a lawsuit" or "bring a lawsuit" for formal phrasing.

Use "lawsuit" (one word) to name a legal case brought to court.
Avoid "law suit" (two words) and "law-suit" (hyphenated) in contemporary writing.
Use "sue" when you need a verb: not "to lawsuit someone."

Core explanation: why it's one word

"Lawsuit" is a settled closed compound (law + suit) that refers to a single concept: a legal action. Dictionaries and legal style guides list it as one word.

When two words form a single, established idea rather than an adjective + noun pairing, English often closes them up: blackboard, courtroom, lawsuit.

If the combined meaning is listed in a dictionary, use the closed form.
If you can naturally say "a [single thing]" (a lawsuit), prefer one word.

Wrong: The factory faces a law suit over emissions.
Right: The factory faces a lawsuit over emissions.

Spacing rules - quick checks to run

Ask: does the pair name one established thing? If yes → one word. If the first word only modifies the second (adjective + noun), keep the space.

Read the phrase aloud: if it feels like one unit with a single stress, prefer closed form.
Try inserting "a": if "a [phrase]" sounds natural as a single object, close it up (a lawsuit).
When in doubt, consult a dictionary or legal usage guide for that specific phrase.

Wrong: She discussed a law suit during class.
Right: She discussed a lawsuit during class.
Contrast: "criminal law" is adjective + noun - keep the space.

Hyphenation and variants

Hyphens often appear in temporary compounds or to avoid ambiguity. "Law-suit" is archaic and unnecessary; modern style guides and dictionaries use "lawsuit."

Avoid "law-suit" in modern prose.
Only hyphenate when a modifier would otherwise be unclear - rare for this term.

Wrong: The board discussed a law-suit.
Right: The board discussed a lawsuit.
Note: Hyphenation can be useful for modifiers (e.g., "pre-trial motions" as a compound modifier), but not for "lawsuit."

Grammar and phrasing: nouns vs. verbs

"Lawsuit" is a noun. The correct verb is "sue." For formal contexts, use "file a lawsuit" or "bring a lawsuit."

Never use "to lawsuit someone." Replace with "sue" or a verb+noun phrase.

Correct verb: sue. Correct noun phrase: file a lawsuit / bring a lawsuit.
Passive forms: be sued; face a lawsuit.

Wrong: They will lawsuit the supplier.
Right: They will sue the supplier / They will file a lawsuit against the supplier.
Wrong: The company will be law-suited.
Right: The company will be sued / The company faces a lawsuit.

Real usage and tone - work, school, and casual examples

Choose terser verbs in conversation and fuller noun phrases in formal writing. Below are practical examples you can copy or adapt.

Work (formal): The company will file a lawsuit to recover contractual damages.
Work (memo): Counsel recommends we prepare for a lawsuit; attach all relevant contracts.
Work (email): Please forward any documents related to the lawsuit by Friday.
School (paper): The lawsuit established a new precedent on data privacy.
School (citation): Cite the lawsuit name, court, and decision year in your bibliography.
School (discussion): In class we analyzed how the lawsuit influenced legislation.
Casual (chat): He's threatening to sue - sounds serious.
Casual (social): They're in a lawsuit with their contractor - total mess.
Casual (text): If they don't fix it, we'll sue / we might file a lawsuit.

Try your own sentence

Test the whole sentence, not just the phrase. Context usually makes the right form obvious.

Examples: wrong → right (copyable swaps)

Replace incorrect spacing or bad verbing with these correct forms. Copy any "Right" sentence directly into your draft.

Wrong: They filed a law suit last week.
Right: They filed a lawsuit last week.
Wrong: The plaintiff prepared a law suit against the manufacturer.
Right: The plaintiff prepared a lawsuit against the manufacturer.
Wrong: We are thinking about a law suit over the missed deadline.
Right: We are thinking about a lawsuit over the missed deadline.
Wrong: The HR manager told him to be ready for a law suit.
Right: The HR manager told him to be ready for a lawsuit.
Wrong: The students watched a documentary about a landmark law suit.
Right: The students watched a documentary about a landmark lawsuit.
Wrong: Don't start a law suit over a neighbor dispute without mediation.
Right: Don't start a lawsuit over a neighbor dispute without mediation.
Wrong: He wants to law suit them for breach of contract.
Right: He wants to sue them for breach of contract / He plans to file a lawsuit for breach of contract.
Wrong: The charity couldn't afford a law suit.
Right: The charity couldn't afford a lawsuit.
Wrong: They threatened a law suit in the review meeting.
Right: They threatened a lawsuit in the review meeting.

Rewrite help - short templates you can paste in

Swap names, dates, and specifics and paste these directly.

Formal (work/legal): "We will file a lawsuit against [Party] for [reason]."
Neutral (academic): "The lawsuit addressed [issue] and resulted in [outcome]."
Casual (conversation): "He's planning to sue [Party]."

Rewrite:
Original: They want to law suit the supplier. → They want to sue the supplier / They intend to file a lawsuit against the supplier.
Rewrite:
Original: She filed a law suit for negligence. → She filed a lawsuit for negligence.
Rewrite:
Original: We will law suit if they don't respond. → We will sue if they don't respond / We will file a lawsuit if they don't respond.

Memory trick and a tiny practice exercise

Mnemonic: picture a single file folder labeled "lawsuit." If you imagine one item, write one word.

Practice: search your document for the two-word string "law suit" and decide for each instance whether to replace with "lawsuit" or rephrase with "sue"/"file a lawsuit."

Visualize one folder labeled "lawsuit."
Search/replace "law suit" across your file, then read each sentence aloud to confirm tone.
Exercise: Find every "law suit" in your draft. Replace with "lawsuit" or "sue" and re-read two sentences to ensure they sound natural.

Similar mistakes to watch for

Other legal and business phrases can trip writers. Check these common traps:

law firm - two words (not "lawfirm").
follow-up (noun/adjective) vs. follow up (verb).
court-martial / court martial - form depends on usage; verify in legal writing.
lawsuit is closed like "blackmail" and "courtroom" - follow dictionary entries for each term.

Wrong: He works at a lawfirm.
Right: He works at a law firm.
Wrong: She scheduled a follow up.
Right: She scheduled a follow-up.
Note: "court-martial" may be hyphenated or closed depending on style - check the legal convention you follow.

FAQ

Is it "law suit" or "lawsuit"?

Use "lawsuit" as one word to mean a legal case brought to court. "Law suit" is incorrect for that meaning.

Can I write "law-suit" with a hyphen?

No. "Law-suit" is outdated. Modern usage and major style guides list "lawsuit" without a hyphen.

Should I say "file a lawsuit" or "sue"?

"File a lawsuit" is formal and suits legal or written contexts. "Sue" is the concise verb for speech and most writing. Choose based on tone.

What if I used "lawsuit" as a verb?

Don't use "lawsuit" as a verb. Use "sue" ("They sued him") or "file/bring a lawsuit" for formal constructions.

How do I quickly fix this across a long document?

Search for the exact string "law suit" (with a space). Replace with "lawsuit" or rewrite as "sue"/"file a lawsuit" based on context, then scan nearby sentences for tone and grammar.

Quick edit tip

Add a search for "law suit" to your proofreading checklist. Use the templates and rewrites above to correct instantly.

Writing tools and dictionaries will flag this spacing error; when in doubt, replace with "sue" or "file a lawsuit."