Par vs. pareja
The Spanish words 'par' and 'pareja' both translate to 'pair' in English but are used in different contexts. Although synonyms in some cases, they express different nuances and are not interchangeable in all situations.
Par
'Par' is primarily used in two ways: referring to the number two or denoting a matching pair, usually of objects.
Tengo un par de zapatos nuevos.
(I have a new pair of shoes.)
Faltan un par de minutos para las doce.
(A couple of minutes are left until twelve.)
Hice un par de intentos antes de tener éxito.
(I made a couple of attempts before succeeding.)
Pareja
'Pareja' usually refers to a pair of people, often implying a romantic or committed relationship, but can also refer to a pair or couple in sports or games.
Carlos y Ana son una pareja muy bonita.
(Carlos and Ana make a beautiful couple.)
Mi pareja y yo vamos a jugar al tenis.
(My partner and I are going to play tennis.)
La película narra la vida de una pareja casada enfrentando problemas.
(The movie portrays the life of a married couple facing problems.)
Summary
In summary, while 'par' and 'pareja' can both translate to 'pair', their usage varies: 'par' is typically used for objects or numerical contexts, whereas 'pareja' often applies to people, frequently but not exclusively implying romantic relationships.