If you feel a little confused or foggy-headed you can say that you are groggy. When you first wake up, you might be groggy until you get up and start moving around.
The adjective groggy comes from the noun grog, which was what the sailors back in the 1700’s called rum diluted with water. Today, grog is slang for any liquor. To feel groggy is to feel drunk, tipsy, weak or dazed. Boxers who’ve sustained numerous blows to the head can get pretty groggy, and they might stagger around the ring — a sign that they are feeling out of it.