binning
n.— «Samsung manages to preserve low-light performance at such resolutions and framerates on such a small sensor using a technique called “binning,” whereby certain pixels are sometimes deactivated and grouped together to help gather light for active pixels. In other words, if you’re, uh, Vlogging in the dark, your webcam stream might look like it’s 720p, but in reality a significant number of pixels might be clumped together. But at least you’ll be able to see them.» —“Samsung Webcam Sensor Handles 720p, Fits Inside Your Laptop Bezel” by John Herrman Gizmodo Dec. 5, 2008. (source: Double-Tongued Dictionary)