Stupid
Definition 1 of 2
Pro Tip 1/3
Negative Connotation
Stupid' often expresses negativity or criticism, so use it with care. Calling someone's idea stupid can be hurtful.
Pro Tip 2/3
Self-Deprecation
Used about oneself, it can convey humility or humor after a mistake. I can't believe I wore two different shoes to work, how stupid of me!
Pro Tip 3/3
Intensity
It can be used to emphasize the extent of a mistake or poor decision. It was stupid of us to go out in the storm without an umbrella.