Sponger at liberty before terrible ordeal (10)
I believe the answer is:
freeloader
'sponger' is the definition.
(synonyms)
'at liberty before terrible ordeal' is the wordplay.
'at liberty' becomes 'free' (similar in meaning).
'before' says to put letters next to each other.
'terrible' indicates an anagram.
'ordeal' anagrammed gives 'loader'.
'free'+'loader'='FREELOADER'
(Other definitions for freeloader that I've seen before include "Sponger (informal)" , "One who takes but never gives" , "One living off others" , "One who gains from others' efforts" , "I'm a sucker" .)