Drink I love in fancy jar (5)
I believe the answer is:
rioja
'drink' is the definition.
(Rioja is an example)
'i love in fancy jar' is the wordplay.
'love' becomes 'o' (In tennis, 'love' means 'zero').
'in' is an insertion indicator.
'fancy' is an anagram indicator.
'i'+'o'='io'
'jar' anagrammed gives 'rja'.
'io' placed inside 'rja' is 'RIOJA'.
(Other definitions for rioja that I've seen before include "Spanish wine variety" , "Spanish wine type" , "Open space (ancient Greek)" , "Wine from northern Spain" , "Spanish drink" .)