A bad start is typical of eccentric (8)
I believe the answer is:
abnormal
'eccentric' is the definition.
(thesaurus)
'a bad start is typical' is the wordplay.
'start' indicates taking the first letters.
'is typical' becomes 'normal' ('normal' can be similar in meaning to 'typical').
The first letter of 'bad' is 'b'.
'a'+'b'+'normal'='ABNORMAL'
'of' acts as a link.
(Other definitions for abnormal that I've seen before include "Unorthodox" , "Non-standard" , "Odd" , "Extraordinary" , "Deviating from the standard" .)