Other forms: recklessnesses
Recklessness is acting without thinking about whether your actions might be dangerous. A speeding driver's recklessness can result in the loss of their license.
While recklessness can be relatively innocent — think of the recklessness of kids doing wild tricks on their skateboards or the recklessness of your friend not doing his homework because he doubts there will really be a math quiz tomorrow. Some kinds of recklessness are more serious, like when your sister accepts a dare to jump off the garage roof onto a trampoline. Recklessness comes from the obsolete reck, "pay heed to something."