1. To procrastinate; to avoid doing something, especially by engaging in some frivolous or diversionary activity. Mark, please stop wasting time and get on with your presentation! Whenever I ask the kids to do their chores, they always find some way or another to waste time. You can tell it's Monday because everyone in the office keeps wasting time over by the water cooler.
2. To spend time engaging in idle, unproductive, or unhelpful activities in order to consume spare time. In this usage, a modifier can be used between "waste" and "time." I remember being a kid and wasting huge amounts of time just strolling around the mall on the weekend. Come meet us for a coffee! We're just wasting time near the station until our train leaves.
3. To do or say something that takes up one's or someone else's time in a useless or unhelpful manner. In this usage, a possessive adjective can be used between "waste" and "time." If you don't have anything useful to contribute, then please just get out of here and stop wasting my time. She's wasting her time trying to convince the boss to increase the budget. I hate it when people hold up the ticket counter at airports with these petty complaints. Don't they realize that they're wasting everyone's time?