Train driver's edgy, in a bad way (5)
I believe the answer is:
drill
'train' is the definition.
(I know that drill is a type of train)
'driver's edgy in a bad way' is the wordplay.
'driver's edgy' becomes 'dr' (I can't explain this - if you can you should give a lot more credence to this answer).
'in a bad way' becomes 'ill' ('in a bad way' can mean seriously ill or injured).
'dr'+'ill'='DRILL'
Can you help me to learn more?
(Other definitions for drill that I've seen before include "Exercise by repeated practice - bore" , "Tool; military training" , "practise" , "Dental assistant" , "Bore; small furrow" .)