Corrupt senator has no time for explanation (6)
I believe the answer is:
reason
'explanation' is the definition.
(reason is a kind of explanation)
'corrupt senator has no time' is the wordplay.
'corrupt' indicates an anagram.
'has no' suggests deleting specific letters.
'time' becomes 't' (abbreviation).
'senator' with 't' taken out is 'senaor'.
'senaor' with letters rearranged gives 'REASON'.
'for' is the link.
(Other definitions for reason that I've seen before include "Motivation or cause" , "Defence" , "Rational motive" , "Logic, sense" , "Cause to perform" .)