coun·​ter·​sue | \ ˈkau̇n-tər-ˌsü How to pronounce countersue (audio) \
variants: or less commonly counter-sue
countersued also counter-sued also countersuing also counter-suing

Definition of countersue

transitive + intransitive

: to sue (someone) in return : to bring a counterclaim against someone They were dissuaded from suing one another because they knew their target likely had patents that covered similar territory and they could be countersued quickly—the legal equivalent of mutually assured destruction.— Steven Levy Appellant countersued, alleging that respondent's interest charges were usurious and that he had breached his fiduciary duty to her.Peterson v. Gustafson

First Known Use of countersue

1898, in the meaning defined above

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The first known use of countersue was in 1898

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Cite this Entry

“Countersue.” Dictionary, Merriam-Webster, Accessed 5 Aug. 2020.

More from Merriam-Webster on countersue

Britannica English: Translation of countersue for Arabic Speakers

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