Stays on track, gracious and firm (8)
I believe the answer is:
corsetry
'stays' is the definition.
(I've seen this before)
'on track gracious and firm' is the wordplay.
'on' means one lot of letters go next to another.
'track' becomes 'ry'.
'gracious' becomes 'cor' (both are exclamations of surprise).
'and' says to put letters next to each other.
'firm' becomes 'set' (I've seen this before).
'cor'+'set'='corset'
'ry' put after 'corset' is 'CORSETRY'.
(Other definitions for corsetry that I've seen before include "stays involved in this" , "that gives me a shapely figure!" .)