In the 1990s, the folks behind Magic: The Gathering had a difficult time coming up with the name for the second set in the game's Mirage block.
It's 1996 and Magic was going into the Mirage block. As the set Mirage (along with its follow-up) are African themed, designers were looking into a proper name for it.
This was by no means the first time designers had a hard time figuring out a name for an expansion, and it wouldn't be the last. After all, this was the same company where they always had some sort of developmental codeword for them as they were being decided.
However, with Mirage, it was different. They needed a name they was within theme, easy to remember and sounded cool. But, as it turned out, this was easier said than done.
The technically first name for the expansion was "Mirage Jr.," however, that name wasn't kept for too long. Instead they went with the name Visions as it was more in line to the theme. But, with that came with another issue as Visions was already the name of a card from Legends that had also been reprinted in Fourth Edition.
Magic had already renamed a previous card called "Mirage" to Shimmer when the Mirage set came out to avoid any sort of confusion.
That's how seriously they took it.
Not wanting to name an expansion that was previously a card name they decided to look into Mirage itself. Citing inspiration from the card Lion's Eye Diamond, they then tried out "Lion's Eye" as the set's name. Again, they felt it was more-or-less the same problem as before.
"Jungle's Edge" was then put forward. This one met the African theme requirement, but it also sounded more like a theme park ride than an expansion. Finally, they looked at their favorite name in total, zeroed in on "Visions" and decided to just name the expansion that, despite there being a card with that same name already.
The result when Visions came out in 1997? Players gave an astounding "This is not confusing at all."
Magic had really thought there was going to be a lot of confusion over it all, but in the end, players knew the difference and really didn't care that it had been a card name before.
Since then, Wizards of the Coast has held the policy of allowing expansions and sets to have the same name as cards. In recent years, expansion have been more unique, with many sets named after the land they take place in, avoiding the problem altogether. Still, the precedent is there to this day just in case it ever comes up again.