In high spirits like the white rabbit captured by writer (6)
I believe the answer is:
elated
'in high spirits' is the definition.
('elated' can be similar in meaning to 'in high spirits')
'the white rabbit captured by writer' is the wordplay.
'the white rabbit' becomes 'late' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'captured by' is an insertion indicator.
'writer' becomes 'ed' (I've seen this in other clues).
'late' going within 'ed' is 'ELATED'.
'like' acts as a link.
Can you help me to learn more?
(Other definitions for elated that I've seen before include "Overjoyed, really delighted" , "Blissful" , "Puffed with success" , "Jubilant, quite chuffed" , "Hyped up" .)