The story
- Middle English · inherited fromconterpart
- English todaycounterpart
From Middle English conterpart, countre parte (“duplicate of a legal document”), equivalent to counter- + part. Compare Old French contrepartie, itself from contre (“facing, opposite”) (from Latin contra (“against”)) + partie (“copy of a person or thing”) (originally past participle of partīre (“to divide”)).
Etymology from Wiktionary, CC BY-SA 4.0.