any of the Scandinavian people who raided the coasts of Europe from the 8th to the 11th centuries
a pirate, and not a name for the people or culture in general
first used by Anglo-Saxons in England for the sea-based Scandinavian or Norse raiders of the Viking Age. Scandinavians or Norse were "Vikings" only when they went on raiding parties. When they returned home, they were simply Norse farmers and fishermen. See related web page.
A profession a Norseman might have taken up. This is the profession of "armed raider". Not all norsemen became vikings but the vast majority of Vikings were norsemen.
Any of the Scandinavian sea rovers and raiders who ravaged the coasts of Europe from the 8th to 10th centuries
The term Viking commonly denotes the ship-borne explorers, traders, and warriors of the Norsemen (literally, men from the north) who originated in Scandinavia and raided the coasts of the British Isles, France and other parts of Europe as far east as the Volga River in Russia from the late 8th century to the 11th century. This period of European history (generally dated to 793–1066) is often referred to as the Viking Age. It may also be used to denote the entire populations of Viking Age Scandinavia and their settlements elsewhere.