TITLE: Why is a ring called a "ring"?
QUESTION [23 upvotes]: Why is a ring called "ring" (or Zahlring in German)?  There seems to (naive) me nothing more ring-like to a ring than there is to a group or a field.  I am particularly interested to learn why the word "ring" seemed appropriate to the founders.  Thanks for educating me!

REPLY [12 votes]: Ring is also an outdated German word for association or coalition - there is probably a better translation, but it means something along those lines. I would guess Hilbert was thinking of this meaning of the word, not the round shiny object usually seen on fingers. 
There is also the word Verband for some algebraic structure http://de.wikipedia.org/wiki/Verband_%28Mathematik%29 for which I do not know the english name, but this notion probably predates ring. A Verband is also a word for association; nowadays, its mainly used in sports - FIFA, UEFA, IOC are Verbände (to increase the confusion, Verband is also the German word for bandage). One might speculate that Hilbert looked for a similar, but different word to describe a similar, but different algebraic structure.