I'm working on a notification platform and found a somewhat amusing bug. My software checks for updates every N minutes, and if there is an update, lets the user know via a non-modal notification. The amusing part is that more than one notification can stack, and I didn't sanity check, left my software for an hour and came back to a handful of notifications all telling me i needed to update.
So I'm working up beefing up the notification center to allow for a single-instance notification. That said, I'm just honestly not sure what to call this new feature of the user interface. In programming Jargon I'd call it a singleton, but the definition doesn't exactly carry over.
singleton
(but I'm also a front-end developer...). Who are you trying to communicate this concept with? If it's for fellow technical people, I'd saysingleton
is likely sufficient. If it's for you to use while speaking to non-technical people, you could subtly define it for them in conversation the first time you use it: "Now, this modal is a singleton, so there can only be one of them showing at a time..."