As @Quentin Gabrel correctly describes, traffic going to your server connected to port 4, would be "egress" traffic, on port 4. However, actually blocking traffic to the server on port 4 might not actually be done on port 4. Much depends on what kind of network device is providing port 4 and how that device is configured. For example, if port 4 is ln a L3 switch and defined as a VLAN access port with the L3 switch having the SVI for that VLAN, an "in" ACL might be used on the SVI to block egress traffic on port 4.
Additionally, again depending on the network device being used, you might also block traffic to the server further "upstream" than the port it's connected to.
Lastly, as much network traffic needs two way communication to work correctly, sometime blocking traffic to your server can be accomplished by blocking traffic from your server.
That aside, as the other poster have also correctly described ingress and egress, logically the same as you ingressing or egressing a building or vehicle.
