Council oddly saying nothing discordant at first (5)
I believe the answer is:
synod
'council' is the definition.
(I know that synod is a type of council)
'oddly saying nothing discordant at first' is the wordplay.
'oddly' indicates alternate letters (letters in the odd-numbered positions are used).
'nothing' becomes 'o' (looks like zero - 0).
'at first' suggests taking the first letters.
The initial letter of 'discordant' is 'd'.
The alternating letters of 'saying' are 'syn'.
'syn'+'o'+'d'='SYNOD'
(Other definitions for synod that I've seen before include "Council of bishops" , "Ecclesiastical assembly" , "Ecclesiastic council" , "Church assembly" , "group of clergymen" .)