Very small females dancing (8)
I believe the answer is:
selfsame
'very' is the definition.
(I know that very can be written as selfsame)
'small females dancing' is the wordplay.
'small' becomes 's' (abbreviation - e.g. clothes size).
'dancing' indicates anagramming the letters.
'females' with letters rearranged gives 'elfsame'.
's'+'elfsame'='SELFSAME'
(Other definitions for selfsame that I've seen before include "Exactly identical" , "The identical kind, not changed or different" .)