We found one dictionary that defines the word not a care in the world:

General (1 matching dictionary)

1. not a care in the world: Cambridge Advanced Learner's Dictionary

Phrases: not have a care in the world, more... ▸ Words similar to not a care in the world ▸ Usage examples for not a care in the world ▸ Idioms related to not a care in the world ▸ Wikipedia articles (New!) ▸ Words that often appear near not a care in the world ▸ Rhymes of not a care in the world ▸ Invented words related to not a care in the world