Spangly frills slipping on horses (6)
I believe the answer is:
equine
'spangly' is the definition.
Although both the answer and definition are adjectives, I can't see how they can define each other.
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for equine that I've seen before include "Like a horse" , "Horsey" , "Horse or donkey, perhaps" , "Horse-like" , "Horsy" .)