The range of tones in a scene, from the darkest, blackest shadows to the brightest, most brilliant highlights, is referred to as dynamic range. The higher the dynamic range in a situation, the more tonal range is present.
A scene with boring, grey midtones, like an elephant against a tan wall, has a low dynamic range, but a scene with vivid highlights and shadows, like a sunset over a gloomy woodland, has a high dynamic range.
Dynamic range is measured in stops in photography, with each stop corresponding to a doubling of light levels. The technicalities don't matter; what matters is that a scene with 10 stops of dynamic range has more tonal diversity than a scene with 5 stops, and so on.