Distressing experience in Delaware during exam (6)
I believe the answer is:
ordeal
'distressing experience' is the definition.
(I've seen this before)
'delaware during exam' is the wordplay.
'delaware' becomes 'de' (standard two letter abbrev).
'during' indicates putting letters inside.
'exam' becomes 'oral' (spoken academic test).
'de' going inside 'oral' is 'ORDEAL'.
'in' acts as a link.
(Other definitions for ordeal that I've seen before include "Tough test in Laredo" , "Long, unpleasant experience" , "A difficult and harrowing experience" , "Torment" , "Prolonged distressing experience" .)