Refers to behaviors without considering the negative outcomes that could follow. He spent money irresponsibly, not thinking about the debt he'd accumulate.
Pro Tip 2/3
Negative Undertone
The word carries a negative feeling, suggesting disapproval of the action. Despite warnings, they partied irresponsibly during the health crisis.
Pro Tip 3/3
Cultural Perceptions
What's ‘irresponsibly’ in one culture may vary in another; it's often subjective. In her culture, going out late was seen as acting irresponsibly.