Borrowed from Middle Low German kogge (“wide, roundish ship”), or from Old Frisian kogge, Middle Dutch kogge, or perhaps from Old Norse kuggi (“sea vessel”) or Swedish kogg (“merchant ship”). The word was first used in Germanic languages to refer to a kind of sail, wide with stumpy, roundish ends; it spread all over the Baltic sea in the 14th-15th centuries with the Hanseatic league, when it was borrowed into Latvian. At first used only as sailors' slang, it spread under Swedish influence in the 17th and 18th century (though one 18th-century author mentions that kuģis was used mostly in Riga, liela laiva “big boat” being used elsewhere); by the mid-19th century, it had become a general term for all kinds of ships in the standard language.