blithely
Definitions
In a way that shows a casual and cheerful indifference considered to be callous or improper.
In a happy, lighthearted, or carefree manner.
Examples
She blithely ignored the warning signs and continued hiking into the storm.
He blithely spent his entire savings on a luxury vacation without considering the consequences.
Synonyms
carelessly heedlessly cheerfully lightheartedly indifferently unconcernedly jauntily
Antonyms
anxiously cautiously solemnly thoughtfully warily seriously apprehensively