ircd version 2.10.02:

NAME
       ircd - The Internet Relay Chat Program Server

SYNOPSIS
       ircd   [-a]  [-c]  [-i]  [-o] [-q] [-t] [-d directory] [-f
              configfile]  [-w  interface]  [-x  debuglevel]  [-h
              hostname] [-p portnum]

DESCRIPTION
       ircd is the server (daemon) program for the Internet Relay
       Chat Program.  The ircd is a server in that  its  function
       is  to "serve" the client program irc(1) with messages and
       commands.  All  commands  and  user  messages  are  passed
       directly  to the ircd for processing and relaying to other
       ircd sites.  The irc(1) program depends upon  there  being
       an  ircd  server  running  somewhere (either on your local
       UNIX site or a remote ircd site)  so  that  it  will  have
       somewhere  to  connect to and thus allow the user to begin
       talking to other users.