verb (used with object), coun·ter·sued, coun·ter·su·ing.
to bring a civil action against (one's complainant).
verb (used without object), coun·ter·sued, coun·ter·su·ing.
to bring a civil action against one's complainant.
Origin of countersue
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Examples from the Web for countersue
But he does countersue the corporations set up by the lawyers of the families that allow them to gain standing in North Carolina.Who Should Kill? Looking for Answers in Erik Prince’s Memoir|Brian Castner|November 22, 2013|DAILY BEAST