Article in German follows singer fully (10)
I believe the answer is:
altogether
'fully' is the definition.
(thesaurus)
'article in german follows singer' is the wordplay.
'article' becomes 'the' (the 'definite article' part of speech**).
'in' means one lot of letters goes inside another.
'german' becomes 'ger' (abbreviation).
'follows' means one lot of letters go next to another.
'singer' becomes 'alto' (alto is a kind of singer).
'the' going within 'ger' is 'gether'.
'gether' after 'alto' is 'ALTOGETHER'.
(Other definitions for altogether that I've seen before include "nude in this" , "Entirely" , "Wholly" , "Completely, on the whole" , "Quite" .)