If you have eight pennies and twelve dimes, the minority — or smaller portion — of your coins are pennies.
If you're left-handed, you are in the minority, because most people are right-handed. That means that right-handed people are the majority (the opposite of minority). Minority is typically used to refer to the smaller of two numbers being compared or to a group of people that is not predominant in a particular country or population. Less commonly, it refers to the time period before someone is of legal age.