Line of descent (8)
I believe the answer is:
pedigree
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">line of descent</span>' is the definition.<br/ ><span class="explanation-format__explanation">(synonyms)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for pedigree that I've seen before include "Pure-bred animal's line of descent" , "(Distinguished) lineage" , "Breeding; descent" , "Distinguished line of ancestors" , "Lineage of purebred animal" .)