Douglas Harper's Etymology Dictionary
a. (''preceded by a cardinal number'') Having a resolution of the specified number of megapixels. n. One million pixels, used as a unit of resolution of digital cameras.
Usage examples of "megapixel".
Manfred pulls out his backup phone and stares at its megapixel display.
Barely twenty-five megapixels in the visible, and worse in the IR and UV spectra.