counterpart UK /ˈkaʊntəˌpɑːt/US /ˈkaʊntɚˌpɑɹt/noun 5verb 1forms 3 noun5 •One who or that which has corresponding functions or characteristics.Her French counterpart attended the meeting via video call.The two companies are working together with their respective counterparts in Asia. •One who or that which resembles another. •Either of two parts that fit together or otherwise complement one another.Those brass knobs and their hollow counterparts interlock perfectly. •Either half of a flattened fossil when the rock has split along the plane of the fossil. •A duplicate of a legal document. verb1 •To counterbalance. formscounterparted · counterparting · counterparts