What does countersue mean?
Countersue is a verb meaning to answer a lawsuit by bringing one of your own. When a person or company is taken to court, they may choose to countersue rather than simply defend themselves, alleging that the original plaintiff has wronged them in turn. The word belongs almost entirely to legal and journalistic language, where it appears in phrases such as 'threatened to countersue' or 'moved to countersue for damages'. Its force lies in the reversal it describes: the accused becomes an accuser, and litigation escalates from one claim into a contest of mutual claims. Closely related is the noun 'countersuit', which names the second lawsuit itself, just as 'suit' names a lawsuit generally. Because countersuing carries connotations of retaliation and escalation, its use often signals a bitter or hard-fought dispute. For readers following business, entertainment, or court news, understanding the term helps make sense of headlines in which both parties end up on opposite sides of two claims.
verbTo bring a lawsuit against someone in response to a lawsuit they have filed, typically as a form of legal retaliation or defence. It is most often used of a defendant who answers the plaintiff's action with a claim of their own.
- To file a lawsuit against someone who has already brought a legal claim against you; to respond to being sued by suing in return.
"After the publisher sued her for breach of contract, the author chose to countersue for unpaid royalties."
"When the contractor sued the homeowner over unpaid invoices, she decided to countersue for shoddy workmanship."
"The tech giant vowed it would countersue any competitor that tried to enforce its patents against it."
In law, the best defence is sometimes another offence — and 'countersue' is exactly that move, turning the defendant's table on the plaintiff.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of countersue
Countersue combines the prefix 'counter-', indicating opposition or a response, with 'sue', meaning to institute legal proceedings. 'Sue' derives ultimately from the Latin verb 'sequi', meaning to follow, which also gave rise to 'suit', 'pursue' and 'ensue' via Old French forms such as 'suir'. The word was formed within English on this pattern, much like other counter- compounds such as 'counterclaim'.
Related word forms
How countersue is actually used
The word is used almost exclusively in legal or journalistic contexts covering litigation. It is typically followed by a direct object naming the person or entity being sued ('countersue someone') or by a 'for' phrase specifying grounds. Register is formal; in everyday conversation speakers more often say they are 'filing a countersuit' than that they 'countersued'.
Easily confused with countersue
A countersuit is the noun naming the second lawsuit itself, while 'countersue' is the verb describing the act of filing it.