blithe BLYTHE adjective WS #7

showing a cheerful, carefree disposition; lighthearted; also can mean showing a casual indifference or lack of concern

1. She has a blithe indifference to anyone's feelings.
2. Everyone loved her for her blithe spirit.
3. The politician made blithe promises he couldn't keep.
4. He makes blithe remarks about serious subjects.
5. The climber showed a blithe disregard for danger.