From the GitHub repo:

* A community fork of a language named after a plant fungus. All of the memory-safe features you love, now with 100% less bureaucracy! *

I assumed with the 'oxide' and 'ferrous' references that Rust's etymology had to do with corrosion, and while that's part of the explanation, it's mostly about fungi [1]

[1] https://stackoverflow.com/questions/16494822/why-is-it-calle...