ἐμπόριον

Emporium comes from the Greek empórion (a place of trade, a market), from émporos (a merchant, literally 'one who travels' — from en, 'in,' and póros, 'passage, journey'). An émporos was specifically a traveling merchant, as opposed to a kápēlos, a local shopkeeper. The distinction mattered: empória were ports designated for foreign trade, while local markets served local needs. Athens's Piraeus was an empórion. The agora was a local market.

Rome adopted the word as emporium. The Emporium of Rome, built along the Tiber River near the Aventine Hill, was the city's main commercial port from the second century BCE. Goods from across the Mediterranean arrived there — grain from Egypt, olive oil from Spain, wine from Gaul. The building was enormous: a continuous portico along the riverbank where ships unloaded and merchants traded. The Testaccio hill nearby is literally made of broken amphora fragments from centuries of trade.

English borrowed emporium in the sixteenth century from Latin. By the nineteenth century, it had become a pretentious word for a large shop. Department stores called themselves 'emporia' to sound grander than they were. The word that once named a designated foreign-trade port was being used to sell haberdashery.

The plural 'emporia' persists in academic usage. In commercial usage, 'emporium' has largely been replaced by 'superstore' and 'megastore' — words that are honest about being about size rather than grandeur. The Greek merchant who traveled by sea would not recognize a suburban shopping center as his empórion.