Ron entertained by Dorothy’s dog in North American city (7)
I believe the answer is:
toronto
'north american city' is the definition.
(I've seen this before)
'ron entertained by dorothy's dog' is the wordplay.
'entertained by' means one lot of letters goes inside another (inserted letters are hosted or entertained).
'dorothy's dog' becomes 'toto' (Dorothy's dog in The Wizard of Oz).
'ron' going within 'toto' is 'TORONTO'.
'in' is the link.
(Other definitions for toronto that I've seen before include "Ontarian capital" , "Capital city of Ontario" , "major city" , "Provincial capital" , "Canadian city" .)