A lawsuit filed against a party that has filed a suit against one.(noun)
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Use "countersuit" in a sentence
"The legal team suing Chevron in Ecuador argued that the restraining order was unnecessary, given the absence of a verdict, and they called the countersuit a blatant attempt to bleed them of money."
"In response, Taymor's lawyers called the countersuit baseless, although not surprising given their previous treatment of her."
"West and Zampella's attorney, Robert M. Schwartz, called the countersuit's claims "false and outrageous.""