Delicate, small, of mini dimension ultimately (5)

I believe the answer is:
elfin
'delicate' is the definition.
(I've seen this before)
'small of mini dimension ultimately' is the wordplay.
'small of' becomes 'elf' (I can't justify this - if you can you should believe this answer much more).
'ultimately' says to take the final letters.
The final letters of 'mini dimension' are 'in'.
'elf'+'in'='ELFIN'
Can you help me to learn more?
(Other definitions for elfin that I've seen before include "Sweet" , "Fairy-like" , "Sprite-like" , "Spritely" , "Resembling one of the little people" .)
