From James Joyce's Ulysses:
By inserting the barrel of an arruginated male key in the hole of an unstable female lock, obtaining a purchase on the bow of the key and turning its wards from right to left, withdrawing a bolt from its staple, pulling inward spasmodically an obsolescent unhinged door and revealing an aperture for free egress and free ingress.
I admit that I've seen this word for the first time "thanks" to an Internet troll, who, as part of spamming a website with their obscene garbage, claimed their fingers are "arruginated" and they need to see a doctor because of this condition; then they proceeded with some inappropriate wordplay, with the punchline being the above quotation from Ulyssess.
I'm mentioning this only because I wonder if this troll didn't use this word in some precise meaning? Or was it only a meaningless gibberish? Is there any precise meaning to this word? The word is not included in any dictionary I can find—not even Wiktionary or the OED.
What does "arruginated" mean? What did James Joyce mean when he was writing it? What does a modern person mean when they use this word?