/usr/share/irssi/help/devoice is in irssi 0.8.17-1+deb8u5.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 | %9Syntax:%9
DEVOICE %|<nicks>
%9Parameters:%9
A list of nicknames to devoice.
%9Description:%9
Removes the channel voice privileges from the given nicknames; you may use
the wildcard character '*' in a nickname.
If a channel is moderated, the users will require a voice or op in order to
be able to send messages to the channel.
%9Examples:%9
/DEVOICE mike
/DEVOICE bob sarah
/DEVOICE jo*n
/DEVOICE *
%9See also:%9 DEOP, MODE, OP, VOICE
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