A bar check sounds like the sort of thing you receive at the end of a long evening of drinking, but that's not what a bar check is.

Among the things that happen at ship room meetings is reviewing each bug that has a proposed fix and deciding whether to accept or reject the fix.

Another thing that happens at ship room meetings is the bar check: The person representing the bug describes the issue and what is known about it so far and asks for a preliminary assessment from the ship room as to whether this is the sort of bug they would approve if a fix were available, in other words, whether it meets the bug bar. If the answer is No, then there is no need to go to the effort of developing a fix for it right now, since you know it would get rejected anyway.