Bolt and key used by a computer operator (6)
I believe the answer is:
escape
'bolt' is the definition.
(I know that bolt is a kind of do a runner)
'key used by a computer operator' is the wordplay.
'key' becomes 'esc' ('Escape' key on a computer keyboard).
'used by' means one lot of letters go next to another.
'a computer operator' becomes 'ape' (I can't explain this - if you can you should give a lot more credence to this answer).
'esc'+'ape'='ESCAPE'
'and' acts as a link.
Can you help me to learn more?
(Other definitions for escape that I've seen before include "Avoid - flight" , "it was great for Steve McQueen!" , "Break loose - flight" , "Duck" , "Decamp" .)