Line Bess changed, being wise (8)
I believe the answer is:
sensible
'wise' is the definition.
(I've seen this before)
'line bess changed' is the wordplay.
'changed' indicates an anagram.
'line'+'bess'='linebess'
'linebess' anagrammed gives 'SENSIBLE'.
'being' is the link.
(Other definitions for sensible that I've seen before include "Rational" , "Reasonable, showing sound judgment" , "Showing good judgment" , "Level-headed" , "Wise, prudent" .)