One inside relaxes and does exams again (6)
I believe the answer is:
resits
'does exams again' is the definition.
I know nothing about this answer so I can't tell whether it can be defined by this definition.
'one inside relaxes' is the wordplay.
'one' becomes 'i' (Roman numeral).
'inside' is an insertion indicator.
'relaxes' becomes 'rests' (I've seen this before).
'i' put inside 'rests' is 'RESITS'.
'and' is the link.
Can you help me to learn more?
(Other definitions for resits that I've seen before include "Does paper over" , "Exams taken for a second time" , "Takes the examination again" , "takes 15 [EXAM] again" .)