The nominal element *w?k- can be identical with Old English w?c ‘dwelling place, lodging, house, village, town, camp, street, lane’, Dutch wijk ‘district in a town’. Old English w?c and Dutch wijk are commonly considered as loanwords from Latin: Latin v?cus means ‘district of a town; minor settlement, village’. The original meaning of *w?king- in this interpretation is ‘inhabitant of a w?c’; the semantical development is supposed to be ‘inhabitant of a w?c ? ‘merchant’ ? ‘merchant / sailor’ ? ‘pirate’. In Dutch the words kopen ‘to buy’ and kapen ‘to act as a privateer’ differ only slightly; kopen is the Franconian continuation, kapen possibly the Frisian continuation of Germanic *kaup-, a loanword from Latin.[18] Admittedly, at least in Old English Eoforwicingas (‘inhabitants of Eoforwic = York’; recorded in the Anglo-Saxon Chronicle, A.D. 918) a derivational suffix -ing is attached to (Eofor)wic; it is, however, hardly likely that Scandinavian Vikings were named on the basis of marketplaces in England.
The nominal element *w?k- to which -ing- was added, can alternatively be identified with Old Norse vík ‘inlet, small bay, creek’ (Old English w?c ‘bay, creek’). If víkingar can be thought of as persons who preferred to stay in small bays or persons who used to go ashore in small bays or to make their raids from there, then the element *w?k- can be conceived as identical with Old Norse vík and Old English w?c ‘bay, etc.’. In the absence of harbours with jetties, however, all sailors had to use bays as anchorage for their ships; therefore it is difficult to understand why Scandinavian pirates were named after a common anchoring habit. Even more important is that Vikings used to operate from islands.
A variant of the above interpretation does not refer to small bays used as anchorages or shelters in general, but to one single bay: Vík, the name of the Oslo Fjord in the South of Norway. In this view Vikings originally were inhabitants of the shores of Vík. Those who combine the word víkingar with the name of the Oslo Fjord have to make clear, how the designation of a small part of the Norwegian population can expand its meaning to denote all Scandinavian pirates.
https://en.wikipedia.org/wiki/Vik
