1 definition by TheSarahSuttonActingAcademy

To make a catastrophic, horrendous error or to be woefully unprepared for a big event; especially when the mistake / lack of preparation could have been easily avoided.

The essence of ‘Borising’ is in the fact that it is unbelievable that the error occurred, and that an average person of relative competence could have identified the problem with ease, before it happened. If the mistake was caused by a genuinely unpredictable event, then it cannot be described as Borising.

Can also be used as a noun, referring to a easily preventable disaster of Biblical proportions. Again, it must be one that simply didn’t need to happen, and a normal functioning human being could have easily prevented.
Look at the state of that! He’s totally Boris’d it!

How could you not see that coming?Are you some kind of Boris?

Come on lads, this is really important. Let’s not make a complete Boris of it.
Get the Boris mug.