emporium (n.)

1580s, "place of trade, mart," from Latin emporium, from Greek emporion "trading place, market," from emporos "merchant," originally "traveler," from assimilated form of en "in" (see en- (2)) + poros "passage, voyage," related to peirein "to pass through," from PIE root *per- (2) "to lead, pass over."

Greek emporos in the "merchant" sense meant especially "one who trades on a large scale, usually but not necessarily by sea" [Buck], as opposed to kapelos "local retail dealer, shopkeeper." Properly, a town which serves as the commercial hub of a region, but by 1830s American English "Grandiloquently applied to a shop or store" [Craigie].