A chasm you keep well away from (5)
I believe the answer is:
avoid
'keep well away from' is the definition.
I can't tell whether this definition defines the answer.
'a chasm' is the wordplay.
'chasm' becomes 'void' (I can't justify this - if you can you should give a lot more credence to this answer).
'a'+'void'='AVOID'
'you' is the link.
Can you help me to learn more?
(Other definitions for avoid that I've seen before include "Get out of" , "Prevent from happening; nullify (law)" , "Keep away from (someone/something)" , "Shy away from" , "invalidate" .)