Good-looking and in good health, more or less (6,4)
I believe the answer is:
pretty well
'more or less' is the definition.
(I've seen this before)
'good-looking and in good health' is the wordplay.
'good-looking' becomes 'pretty' (I've seen this before).
'and' means one lot of letters go next to another.
'in good health' becomes 'well' ('well' can be similar in meaning to 'in good health').
'pretty'+'well'='PRETTY WELL'
(Other definitions for pretty well that I've seen before include "Sort of" , "More or less" , "Aim of dressing in Derbyshire" , "Practically" , "Close to" .)