Asian joint said to be cramped (4)
I believe the answer is:
tiny
'be cramped' is the definition.
(thesaurus)
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for tiny that I've seen before include "Wee" , "Quite insignificant" , "Microscopic" , "with sharp points?" , "Underdeveloped" .)