silence is a server side ignore used by some ircds such as unrealircd
it ignores all communication (messages, notices, ctcp, etc.) both personal and channel from specified user, this is different from such features as "callerid" which ignores only personal privmsgs
Ignores messages from a user or list of users at the Server itself.
Syntax: SILENCE +nickname (Adds a nickname to SILENCE list)
SILENCE -nickname (Removes a nickname from the SILENCE list)
SILENCE (Lists the current SILENCE list)
just a quick note
using eggdrop's ignore still allows the bot to be flooded off the ircd by filling the connection's receive queue
silence stops all traffic from that nick to the bot, making notice, invite, ctcp, and message floods impossible