IPA: /ˈrɛk.ləs.li/
KK: /ˈrɛk.ləs.li/
In a way that shows a lack of care about the consequences of actions, often leading to danger or harm.
He drove recklessly, ignoring the speed limits and traffic signals.
Recklessly → It is formed from "reck" (from Old English *reccean*, meaning to care or be concerned) and "-less" (meaning without). The word "recklessly" means without care or concern for the consequences of one's actions.
Think of someone who doesn't 'care' ('reck') about the results of their actions, which is why they act 'without' ('-less') caution.