The whole topic of color management can get pretty dry and technical, but stick with it because there’s information here that’s useful and puts lots of other things in context.
Gamut
Gamut is another word for the range of colors that fit in a 'color space'. So you would say, for example, that Adobe RGB has a wider 'gamut' than sRGB, or that a high-end monitor for photographers can display the Adobe RGB gamut.