Badly lame in serving (6)
I believe the answer is:
menial
'serving' is the definition.
(thesaurus)
'badly lame in' is the wordplay.
'badly' indicates an anagram (letters in the wrong order).
'lame'+'in'='lamein'
'lamein' with letters rearranged gives 'MENIAL'.
(Other definitions for menial that I've seen before include "Subservient, lowly" , "(Of work) unskilled" , "A drudge" , "Humble - servant" , "Servile of lowly" .)