In two different companies I’ve seen people refer to “the database” when they actually mean a spreadsheet. That’s not just a terminology mixup, these things were super complex, with pseudo-relational tables, lookups, links to other files etc. The sort of thing that should be in an actual database, that has less chance of breaking in obscure ways when someone inserts a row or types a value over a formula. It was actually pretty impressive, in an “impending doom at any moment” kind of way.

Also had one where there was a spreadsheet of everyone in the business top to bottom, shared by HR and IT. Both groups needed a list of staff, so why not just keep one, right? This thing had personal details like home address and medical conditions, plus things like salary (inc garnishments), performance management notes etc, as well as of course their username and password (which was assigned to them and they couldn’t change) and security questions and answers. It didn’t even have a password on the file. I noped tf out of that place as quickly as I could, but for reasons even worse than that stupid spreadsheet.