Lusty saint in error, ignoring leader (6)
I believe the answer is:
strong
'lusty' is the definition.
(thesaurus)
'saint in error ignoring leader' is the wordplay.
'saint' becomes 'st' (abbreviation).
'in error' becomes 'wrong' (I've seen this in another clue).
'ignoring leader' means to remove the first letter.
'wrong' with its initial letter taken off is 'rong'.
'st'+'rong'='STRONG'
(Other definitions for strong that I've seen before include "Powerful; highly alcoholic" , "strong" , "muscular or concentrated" , "Great in power" , "Resilient" .)