Tomboyish old Disney jockeys feeding horse more than once (9)
I believe the answer is:
hoydenish
'tomboyish' is the definition.
(synonyms)
'old disney jockeys feeding horse more than once' is the wordplay.
'old' becomes 'o' (common abbreviation eg in OE for Old English).
'jockeys' indicates anagramming the letters.
'feeding' indicates putting letters inside.
'horse' becomes 'h' (synonyms).
'more than once' indicates the doubling of some letters.
'disney' with letters rearranged gives 'ydenis'.
'o'+'ydenis'='oydenis'
'h' doubled is 'hh'.
'oydenis' inserted inside 'hh' is 'HOYDENISH'.
(Other definitions for hoydenish that I've seen before include "Like high-spirited lass" , "Like a romp" .)