Tough German conceals neurotic fear (8)

I believe the answer is:

gangster

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'tough' is the definition.
(thesaurus)

'german conceals neurotic fear' is the wordplay.
'german' becomes 'ger' (abbreviation).
'conceals' indicates putting letters inside.
'neurotic fear' becomes 'angst' (I am not sure about the 'neurotic' bit.).
'ger' placed around 'angst' is 'GANGSTER'.

Can you help me to learn more?

(Other definitions for gangster that I've seen before include "Villain" , "Hoodlum" , "Member of a mob like Al Capone" , "Wise guy" , "Organised criminal" .)

I've seen this clue in The Guardian and The Sun.

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