Engineers getting wrong sort of answer (6)
I believe the answer is:
retort
'sort of answer' is the definition.
'engineers getting wrong' is the wordplay.
'engineers' becomes 're' (Royal Engineers).
'getting' means one lot of letters go next to another.
'wrong' becomes 'tort' (legal term).
're'+'tort'='RETORT'
(Other definitions for retort that I've seen before include "Long-necked glass vessel" , "Quick rejoinder" , "Sharp response; lab item" , "Witty answer" , "Sharp rejoinder" .)