Some brat, ticklish, using loft (5)
I believe the answer is:
attic
'loft' is the definition.
(synonyms)
'some brat ticklish using' is the wordplay.
'some' says the answer is hidden in the clue (some parts of the word are used).
'ATTIC' can be found hidden inside 'brat ticklish using'.
(Other definitions for attic that I've seen before include "Athenian Greek" , "Athenian - garret" , "Top chamber" , "from Greece" , "Dusty room" .)