Just in case you ever get involved in a woodworking trivia contest, here’s the question of the day. What’s the difference between a dado and a groove? Or, you might ask, is there a difference at all? The answer is yes, there is a difference. You can find out what it is right here so you’ll be ready to stump your woodworking buddies with this question.
So do you cut groves or dados in plywood?
With plywood the same nomenclature applies. You would simply reference the face veneer to determine whether the recess would be considered a groove or a dado.
I would suggest that a dado is a slot cut for a snug fit, and a groove is a slot cut for a loose fit (especially when thinking about the bottom of a drawer).
my understanding, as an ameteur, is that a dado goes across the grain, and a groove goes with the grain.