1. To trip and almost fall as a result of bumping into someone or something. I stumbled over a box someone had set down in the hallway. She stumbled over the people sleeping on the living room floor as she made her way to the kitchen.

2. To push and shove someone else out of the way, as to get some place or in order to do something. People were stumbling over each other to get their pictures taken with the famous actor. The kids stumbled over each other to get into the ice cream parlor.

3. To have difficulty saying something clearly or correctly; to stutter or stammer while trying to say something. The actors stumbled over their lines and talked over each other constantly. They really needed more time to rehearse. He tried asking her on a date, but he was so nervous that he kept stumbling over his words.