Other forms: eccentricities
Eccentricity is strange, out-of-the-ordinary, sometimes weirdly attractive behavior or dress. Sleeping with your boots on is pretty normal if you're a cowboy, but leaving them on for bedtime in your city apartment, that shows some eccentricity.
Eccentricity goes back to the Greek ekkentros, meaning "off center," and when you describe people as being a little "off," you might be talking about their eccentricity or behavior that's a bit abnormal. An eccentricity might be some really small character trait, like eating all of the green food on your plate first, or a large and very obvious characteristic, as when you ride a donkey to your suburban school instead of taking the bus.