Relating to or characteristic of the Gordius genus; used metaphorically to describe something extremely complex or knotted (from 'Gordian knot').
From Gordius, the genus of horsehair worms, and also referencing the legendary Gordian knot from ancient Phrygian history—the two meanings have separate etymologies that converged.
It's brilliant that 'Gordian' works both for actual worms AND for the famous knot—both refer to something impossibly tangled, whether it's myth or parasitology.
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