Happy pedestrianised zone finally enclosed (8)
I believe the answer is:
carefree
'happy' is the definition.
(synonyms)
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for carefree that I've seen before include "without worrying?" , "Take a chair" , "Happy and blithe - no worries" , "Jaunty" , "Not worried" .)