Ascendancy of bent copper near end (13)
I believe the answer is:
preponderance
'ascendancy' is the definition.
(thesaurus)
'bent copper near end' is the wordplay.
'bent' is an anagram indicator.
'copper'+'near'+'end'='coppernearend'
'coppernearend' is an anagram of 'PREPONDERANCE'.
'of' is the link.
(Other definitions for preponderance that I've seen before include "Superiority in numbers" , "In majority of" , "An excess in number or quantity" , "Predominance" , "Greater numbers" .)