Where test involved grasping a flame (10)
I believe the answer is:
sweetheart
'flame' is the definition.
(thesaurus)
'where test involved grasping a' is the wordplay.
'involved' is an anagram indicator (involved can mean confusing or complex).
'grasping' indicates putting letters inside.
'where'+'test'='wheretest'
'wheretest' with letters rearranged gives 'sweethert'.
'sweethert' enclosing 'a' is 'SWEETHEART'.
(Other definitions for sweetheart that I've seen before include "Juliet had one" , "baby" , "Darling" , "Beloved" , "Love" .)