Chutzpah mainly precedes row in border (8)
I believe the answer is:
frontier
'border' is the definition.
(I've seen this before)
'chutzpah mainly precedes row' is the wordplay.
'chutzpah' becomes 'front'.
'mainly' means to remove the last letter.
'precedes' says to put letters next to each other.
'row' becomes 'tier' (tier is a kind of row**).
'front' with its final letter taken away is 'fron'.
'fron'+'tier'='FRONTIER'
'in' acts as a link.
(Other definitions for frontier that I've seen before include "Border separating two countries" , "Verge" , "Limit" , "Marches" , "International boundary" .)