counterpart

Etymology

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”)).

Pronunciation

• (UK) IPA^(key): /ˈkaʊntəˌpɑːt/
• (US) IPA^(key): /ˈkaʊntɚˌpɑɹt/

• Audio (US):

  (file)

Noun

counterpart (plural counterparts)

1. Either of two parts that fit together, or complement one another.

   Those brass knobs and their hollow counterparts interlock perfectly.

   • 2012 November 7, Matt Bai, “Winning a Second Term, Obama Will Confront Familiar Headwinds”, in New York Times‎:

     Mr. Obama never found a generational counterpart among conservatives in Congress like Paul D. Ryan or Eric Cantor; instead, there was a mutual animosity.

2. (law) A duplicate of a legal document.
3. One who or that which resembles another. (Can we add an example for this sense?)

   Synonyms: see Thesaurus:counterpart

4. One who or that which has corresponding functions or characteristics.
   • 1962 July, “Talking of Trains: The new all-line timetable”, in Modern Railways, page 10:

     Its incompleteness in this respect makes the timetable of less value than some of its Continental counterparts, such as the French Horaires Mayeux; nevertheless, it is fair value at 5s.

   • 2011 November 12, “International friendly: England 1-0 Spain”, in BBC Sport‎:

     England's attacking impetus was limited to one shot from Lampard that was comfortably collected by keeper Iker Casillas, but for all Spain's domination of the ball his England counterpart Joe Hart was unemployed.

5. (paleontology) Either half of a flattened fossil when the rock has split along the plane of the fossil.

Verb

counterpart (third-person singular simple present counterparts, present participle counterparting, simple past and past participle counterparted)

1. (transitive) To counterbalance. (Can we add an example for this sense?)