Used advantage to secure right to ground-breaking (5-5)
I believe the answer is:
'ground-breaking' is the definition.
Both the definition and answer are adjectives.
Maybe there's a link between them I don't understand?
'used advantage to secure right' is the wordplay.
'used' is an anagram indicator.
'to secure' is an insertion indicator (inserted letters are secured inside).
'right' becomes 'r' (abbreviation).
'advantage' anagrammed gives 'avantgade'.
'avantgade' placed around 'r' is 'AVANT-GARDE'.
'to' acts as a link.
Can you help me to learn more?
(Other definitions for avant-garde that I've seen before include "New and experimental" , "Daringly innovative or unconventional" , "Radical - daring" , "In the arts, radically new and daring" , "Experimental (art)" .)