Get rid of eccentric form of gambling (11)
I believe the answer is:
scratchcard
'form of gambling' is the definition.
'scratchcard' can be an answer for 'form' (I have seen 'form of lottery' mean 'scratchcard' so perhaps 'form' could also mean 'scratchcard'). I'm unsure of the 'of gambling' bit.
'get rid of eccentric' is the wordplay.
'get rid of' becomes 'scratch' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'eccentric' becomes 'card' (I've seen this in other clues).
'scratch'+'card'='SCRATCHCARD'
Can you help me to learn more?
(Other definitions for scratchcard that I've seen before include "Rubbed lottery ticket" , "Gambler's investment rubbed with a coin" , "Ticket for instant lottery" , "form of lottery" .)