Softlock

A softlock occurs when the game is put into a state where, though it has not crashed or ceased functioning, it has been put into a state from which there is no way to exit without resetting the console.

Known Softlocks

Repeatedly bonking within a glitchy wall
Getting stuck in a Black Room of Death
Activating a death, star, or sign text cutscene at the same time as a specific type of star activation cutscene (mainly item box stars)
Being grabbed by Heave-Ho or Chuckya while releasing its clone
Being grabbed by Chuckya while in timestop
Collecting a star in vertical wind
Activating a star in a PU