The adjective '괜찮다' means:
형용사 (adjective)
별로 나쁘지 않고 보통 이상이다. Not bad and above average.
When you look at the adjective '편찮다', you can know it is from another adjective '편하다' as '편찮다' is a contracted from of '편치 않다', which is again short for '편하지 않다'.
What is the etymology of '괜찮다'?