Member of secret fraternity is unusual bloke (9)
I believe the answer is:
oddfellow
'member of secret fraternity' is the definition.
'oddfellow' can be an answer for 'member' (I have seen 'Member of fraternity' mean 'oddfellow' so perhaps 'member' could also mean 'oddfellow'). I am not certain of the 'of secret fraternity' bit.
'unusual bloke' is the wordplay.
'unusual' becomes 'odd' (similar in meaning).
'bloke' becomes 'fellow' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'odd'+'fellow'='ODDFELLOW'
'is' acts as a link.
Can you help me to learn more?
(Other definitions for oddfellow that I've seen before include "member of secret society" , "one of a fraternity" , "fraternal member" , "Member of fraternity" , "Member of friendly society (funny chap!)" .)