So turned again and shot (4)
I believe the answer is:
ergo
'so' is the definition.
('ergo' can be a synonym of 'so')
'turned again and shot' is the wordplay.
'turned' says the letters should be written in reverse.
'again' becomes 're'.
'and' says to put letters next to each other.
'shot' becomes 'go' (I've seen this in other clues).
're' reversed gives 'er'.
'er'+'go'='ERGO'
(Other definitions for ergo that I've seen before include "Therefore - what a goer" , "'Cogito, ---- sum'" , "Thus" , "Therefore (Latin)" , "as a consequence" .)