Excessively boring, tedious, or dull; repetitive; of an activity, etc., lacking any interest or variety that might serve as intellectual stimulation
The story described the main character's wristwatch in mind-numbing detail.
If you describe an event or experience as mind-numbing, you mean that it is so bad, boring, or great in extent that you are unable to think about it clearly
If you describe an event or experience as mind-numbing, you mean that it is so bad, boring, or great in extent that you are unable to think about it clearly. It was another day of mind-numbing tedium. + mind-numbingly mind-numbingly a mind-numbingly boring sport