v.1. To pack or fill something completely with a large quantity of something: I can't eat any more—that big meal stuffed me up. We stuffed up the closet with all our old magazines.
2. To cause someone's sinus or nasal passages to be clogged: The flu really stuffed me up. I was stuffed up with a bad cold.
3. To be clogged. Used especially of sinus and nasal passages: My nose stuffs up whenever I catch a cold.