Anonymous salesmen behaving improperly (8)
I believe the answer is:
nameless
'anonymous' is the definition.
('nameless' can be similar in meaning to 'anonymous')
'salesmen behaving improperly' is the wordplay.
'behaving improperly' indicates an anagram (I've seen this in other clues).
'salesmen' is an anagram of 'NAMELESS'.
(Other definitions for nameless that I've seen before include "This undistinguished" , "Difficult to describe" , "like the guy in the spaghetti movies?" , "Untitled" , "not easily identified?" .)