Touched a mark back of Bourke on the first of December (7)

'touched' is the definition.
(abutting is a kind of touching)

'a mark back of bourke on the first of december' is the wordplay.
'a mark' becomes 'abut' (I am not sure about this - if you are sure you should believe this answer much more).
'back of' indicates one should take the final letters.
'on' is a charade indicator (letters next to each other).
'the' becomes 't' (the is pronounced as a 't' sound in some dialects).
'first of december' becomes 'd' (ast letter of 'december').
The final letter of 'bourke' is 'e'.
'e' put after 't' is 'te'.
'abut'+'te'+'d'='ABUTTED'

Can you help me to learn more?