Promise to keep silent on most of official questions put to voters (9)
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I believe the answer is:
referenda
'voters' is the definition.
Although both the answer and definition are plural nouns, I can't see how they can define each other.
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for referenda that I've seen before include "General votes" , "National votes or plebiscites (9)" , "Votes put to country generally 9)" , "National ballots on specific issues" , "National polls as for amendments of constitution" .)
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