German's relative has handy habit around food (7)
I believe the answer is:
yiddish
'german's relative' is the definition.
(language related to German)
'handy habit around food' is the wordplay.
'handy habit' becomes 'DIY' (Do It Yourself work).
'around' says the letters should be written backwards.
'food' becomes 'dish' (dish is a kind of food).
'diy' back-to-front is 'yid'.
'yid'+'dish'='YIDDISH'
'has' acts as a link.
(Other definitions for yiddish that I've seen before include "European Jews' vernacular" , "Language used by European Jews" , "Vernacular Jewish language" , "Dishy Di (anag.)" , "Old Jewish language" .)