A bout is a fight. If you want to be a boxer, start with some easy bouts before challenging the champ.
A bout is a period of time in which something intense happens, like fighting, binging, or being sick, and comes from the word for bending, or going round in a circle. We usually use it these days for something you wouldn't want to go on for too long of a time. If the full moon makes you crazy, you might suffer a bout of madness.