be eating (one's) dust
To be outperformed or outrun by one, usually by a very wide margin; to be far behind one. The image is that of running into the cloud of dust that has been kicked up by the runner ahead of one. We've been eating the competitor's dust since they released their new line of devices.
be eating (someone's) dust
mainly AMERICANIn a competitive situation, if you are eating dust or are eating someone's dust, they are doing much better than you. Aladdin has proved to be the most successful animated film of all time, leaving blockbusters like Home Alone 2 eating its dust. Compared to other race games, this one is eating dust. Note: If you are riding behind another horse in a race, you have the dust kicked up by the other horse in your face.