Retire, worried by look from this layabout (8)
I believe the answer is:
loiterer
'this layabout' is the definition.
(loiterer is a kind of layabout)
'retire worried by look' is the wordplay.
'worried' indicates an anagram.
'by' is a charade indicator (letters next to each other).
'look' becomes 'lo'.
'retire' anagrammed gives 'iterer'.
'iterer' put after 'lo' is 'LOITERER'.
'from' acts as a link.
(Other definitions for loiterer that I've seen before include "One skulks around" , "He hangs around idly" , "One hanging around" , "layabout" , "Person hanging around suspiciously" .)