Learn English – Etymology of “magma” in abstract algebra

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Magma is one of those beautiful words of Greek origin (μάγμα) that arouses the child and the wild in me, making me think of volcanoes. I just found out, though, that it is also used in mathematics to mean a type of algebraic structure (a set paired with a binary operation on it)! I am very curious how this name was picked for this particular algebraic structure (which is also called by groupoid). Wikipedia attributes the coining of this term to Nicolas Bourbaki, but does not mention how they arrived at such a name. I have not been able to find the specific etymology of this sense anywhere else. What is its origin?

Best Answer

It may be a pun. Looking up magma in the French wikipedia*, another name for magma in French is groupoïde de Ore. Here Ore is a Norwegian mathematician, but ore in English is mineral-bearing rock, whereas magma (in both English and French) is molten rock.

Would Bourbaki have based a mathematical term on this pun? I'm not in a good position to judge; maybe somebody else could comment on this.

* Since Bourbaki was a pen name used by a group of French mathematicians, this is the right language to search in.
There is also a groupoïde de Brandt, also called a groupoid in English, which would explain why Bourbaki felt compelled to coin a new name.