As a noun recklessness
is the state or quality of being reckless or heedless, of taking unnecessary risks.
As an adjective negligent is
negligent (culpable due to negligence).
* (l), (l) (obsolete)
The state or quality of being reckless or heedless, of taking unnecessary risks.
- His recklessness repeatedly put him in danger.
Careless, without appropriate or sufficient attention.
(legal) Culpable due to negligence.
* See also