I find it weird that English apparently doesn’t have an everyday word for marine bioluminescence. It’s such an academic word. What would traditional sailors and fishermen have called it? In my language (Norwegian) we call it «morild» (sea-fire).

> It’s such an academic word.

It's not even an early academic word; by its construction you can see that it postdates the period when scientists would have been expected to know Greek or Latin. etymonline dates it to 1909.

There are some interesting mentions in the "history" section of the wikipedia article:

> In 1920, the American zoologist E. Newton Harvey published a monograph, The Nature of Animal Light, summarizing early work on bioluminescence. Harvey notes that Aristotle mentions light produced by dead fish and flesh, and that both Aristotle and Pliny the Elder (in his Natural History) mention light from damp wood.

> He records that Robert Boyle experimented on these light sources, and showed that both they and the glowworm require air for light to be produced. Harvey notes that in 1753, J. Baker identified the flagellate Noctiluca "as a luminous animal" "just visible to the naked eye", and in 1854 Johann Florian Heller (1813–1871) identified strands (hyphae) of fungi as the source of light in dead wood.

Had there been a term in common use, it probably would have been adopted for scientific use too. But if for some reason that didn't happen, it looks like The Nature of Animal Light would be your best bet for finding out what peasants called it.

I suspect that Aristotle and Pliny the Elder both called it "light", and that would be my first guess for what English miners and fishermen called it too.