Espadarte vs. peixe-espada
While both espadarte and peixe-espada can be translated as swordfish, their usage reveals a significant regional difference between European and Brazilian Portuguese, and can even refer to entirely different species of fish.
Espadarte
A2This is the primary and most accurate term for swordfish (the species *Xiphias gladius*) in European Portuguese. It is used in formal, scientific, and everyday contexts, including restaurants, fish markets, and marine biology in Portugal.
O espadarte é um dos peixes mais rápidos do oceano.
(The swordfish is one of the fastest fish in the ocean.)
Para o jantar, vamos comer um bife de espadarte grelhado com batatas.
(For dinner, we are going to have a grilled swordfish steak with potatoes.)
A pesca do espadarte é uma atividade económica importante nos Açores.
(Swordfish fishing is an important economic activity in the Azores.)
Aquele documentário mostrava a caça de um espadarte por um grupo de orcas.
(That documentary showed a group of orcas hunting a swordfish.)
Peixe-espada
B1In Brazilian Portuguese, peixe-espada is the common name for the swordfish (*Xiphias gladius*). However, in European Portuguese, especially in the Madeira islands, peixe-espada refers to a completely different fish: the black scabbardfish (*Aphanopus carbo*), which is long, black, and eel-like.
No Brasil, é comum encontrar moqueca de peixe-espada nos restaurantes.
(In Brazil, it is common to find swordfish moqueca in restaurants.)
A especialidade da Madeira é o peixe-espada preto frito com banana.
(The specialty of Madeira is fried black scabbardfish with banana.)
O turista ficou confuso ao pedir peixe-espada em Lisboa e não receber o que esperava.
(The tourist was confused when he ordered scabbardfish in Lisbon and did not receive what he was expecting.)
Ele me disse que o peixe-espada tem uma carne branca e firme.
(He told me that swordfish has a white and firm flesh.)
Summary
The key difference is regional. Use espadarte for swordfish (*Xiphias gladius*) in European Portuguese. Use peixe-espada for swordfish in Brazilian Portuguese. Be aware that in Portugal, especially Madeira, peixe-espada refers to the black scabbardfish, a distinct local delicacy.