I go on horse smell changing according to one’s position? (10)

I believe the answer is:

iridescent

'changing according to one's position?' is the definition.
(iridescent things sparkle depending on the angle)

'i go on horse smell' is the wordplay.
'go on horse' becomes 'ride' (ride on a horse).
'smell' becomes 'scent' (scenting is a kind of smelling).
'i'+'ride'+'scent'='IRIDESCENT'

(Other definitions for iridescent that I've seen before include "flashing colours" , "Like a rainbow" , "Showing luminous colours" , "Shimmering with rainbow colours (anag of 1 across, 9 and 23)" , "Sparkling" .)

I've seen this clue in The Times.

Want a hint initially instead of a full solution? Install my app