Compound in Hungary ideal for torture (6)
I believe the answer is:
halide
'compound' is the definition.
(halide is a kind of compound)
'hungary ideal for torture' is the wordplay.
'hungary' becomes 'h' (abbreviation used in vehicle registration codes**).
'for torture' indicates an anagram (the original letter order must be damaged ).
'ideal' is an anagram of 'alide'.
'h'+'alide'='HALIDE'
'in' acts as a link.
(Other definitions for halide that I've seen before include "Chemical containing e g chlorine" , "Halogen compound" .)