Ten months since present time (4)
I believe the answer is:
xmas
'present time' is the definition.
(I've seen this in another clue)
'ten months since' is the wordplay.
'ten' becomes 'X' (Roman numeral).
'months' becomes 'm'.
'since' becomes 'as' (I've seen this in other clues).
'x'+'m'+'as'='XMAS'
(Other definitions for xmas that I've seen before include "Brief version of the Nativity, beginning with Greek letter" , "December festival" , "Winter festival (informal)" , "Short celebration" , "Christmas (informal)" .)