carelessly
adv. B1 Intermediate US //ˈkɛɹɫəsɫi// UK //kˈeələsli// care·less·ly
adv. in a way that shows you do not care about being careful or about the people and things around you.
adv. in a manner that lacks attention to detail or consideration for others and their safety.
He carelessly left his keys on the table.
She carelessly dropped the fragile vase, which shattered into several sharp pieces on the floor.
The manager was reprimanded for carelessly neglecting the safety protocols, which ultimately led to a minor but preventable accident in the warehouse.
From careless + -ly.