That, my friends, is a word that you want to do everything in your power to avoid, while creating a character.
All of your characters... ALL of them, have some clichés that technically you should avoid. Now, there are some exceptions. I have several clichés in my novel... But, I have put my own unique twist on them (because the features of one of my characters is crucial to the plot-line).
Sidenote: Sometimes, authors do some of these on purpose, for effect.
Here is a list of some of the clichés I have found, which go with each character.
Main Character - Usually strong. Especially if your character is female. Usually exceptionally good-looking.
E.g. Tris from Divergent.
Sidekick - Often times... There are two types... And when I say this, I hope you realize that I'm talking about a girl ;). The first type is usually drop-dead gorgeous... You know... Perfectly done blond hair, full lips, sharply defined facial features, and a 'perfect' body. But the catch is that she can't do anything. She's about as dumb as they get. The second type is sometimes still drop-dead gorgeous, but more than not, their appearance doesn't matter, because they are the smartest person you will ever meet.
E.g. type #1: Lucy from The Life of Ellie Sweet
E.g. type #2: Annabeth from The Lightning Thief
Antagonist - Same thing with the sidekick... Only this person (male or female) will be a person of influence. They are important. And yeah.... Usually, they are really good looking.
E.g. Four from Divergent
Villain - Red/black/weirdly-glowing-eyes. Black hair. Some sort of pet, which is reallyyyyy important to the story.
E.g. Maleficent from (I know... It's a movie, but it still counts.) Maleficent
So... Along with some good description, and avoiding these clichés, you can have some super 'real' characters!