An icon is a symbol. It can be literal—–like the little trashcan on your computer screen—–or metaphorical––as in a singer so well known by ten-year-olds, he's called a pre-teen pop icon.
Icon comes to us from the Greek word eikenai, meaning "to seem or to be like." In certain religions, statues of religious figures are referred to as icons––because they are prayed to as if they were the thing they represent. Icon can also describe a person closely linked to an idea. Mahatma Gandhi is revered as an icon of peace and humanity, while Adolf Hitler is reviled as an icon of violence and hatred.