squeegee
A tool with a rubber edge used to wipe off water.
A squeegee is a cleaning tool with a flat rubber blade attached to a handle, used to wipe water off smooth surfaces. You've probably seen someone using a squeegee to clean windows: they spray the glass with soapy water, then pull the rubber blade down in smooth strokes, pushing all the water and dirt to the bottom where it drips away. The rubber edge fits snugly against the glass, leaving it clear and streak-free.
Window washers on tall buildings use squeegees attached to long poles. After you take a shower, you might use a small squeegee to wipe water droplets off the glass door so it doesn't leave spots. Gas stations often have squeegees near the pumps so drivers can clean their windshields.
Some people also use squeegees for unexpected tasks, like smoothing out air bubbles when applying stickers to car windows or spreading paint evenly on certain surfaces. The key is always that firm rubber edge that pushes liquid across a smooth surface and leaves it clean and dry.