Piggish German's tall and thin (6)
I believe the answer is:
greedy
'piggish' is the definition.
(thesaurus)
'german's tall and thin' is the wordplay.
'german' becomes 'g' (abbreviation).
'tall and thin' becomes 'reedy' (I've seen this before).
'g'+'reedy'='GREEDY'
(Other definitions for greedy that I've seen before include "Over-desirous of food" , "Covetous, avaricious" , "Having a voracious appetite" , "Avaricious and acquisitive" , "Grasping" .)