club: [13] The original meaning of club is ‘thick heavy stick for hitting people’; it was borrowed from Old Norse klubba. The sense ‘association’ developed in the 17th century, apparently originally as a verb. To club together seems to have been based on the notion of ‘forming into a mass like the thickened end of a club’: ‘Two such worlds must club together and become one’, Nathaniel Fairfax, The bulk and selvedge of the world 1674. Hence the noun club, which originally signified simply a ‘get-together’, typically in a tavern, but by the end of the 17th century seems to have become more of a formalized concept, with members and rules. [club etymology, club origin, 英语词源]