Some ignore site for further examination (5)
I believe the answer is:
resit
'further examination' is the definition.
(I've seen this before)
'some ignore site for' is the wordplay.
'some' indicates a hidden word (some parts of the word are used).
'RESIT' can be found hidden inside 'ignore site for'.
(Other definitions for resit that I've seen before include "Enquiring intrusively (into person's affairs)" , "Take examination again" , "tested again" , "Retake exam" , "repeated test" .)