Multi-faceted figure formed by dance horde, dancing (10)
I believe the answer is:
decahedron
'multi-faceted figure' is the definition.
'dance horde dancing' is the wordplay.
'dancing' is an anagram indicator.
'dance'+'horde'='dancehorde'
'dancehorde' anagrammed gives 'DECAHEDRON'.
'formed by' acts as a link.
(Other definitions for decahedron that I've seen before include "Ten-faced solid" , "Ten-faced figure" , "Solid figure with ten plane faces" .)