I think this is a very basic question but I need some understanding.
What does a port mean in freebsd?
In regards to software, When using "port" as a noun in regards to FreeBSD, it is a piece of software that has been modified so it will easily compile, install and run. FreeBSD comes with a set of directories that contain thousands of such pieces of software located in
Precompiled versions of the software are usually available as "packages". Once a port is installed, the package management system allows you to maintain the software semi-efficiently.
Ports are usually not written by the FreeBSD Foundation or released with the operating system itself. You can browse the list online on their website.
A port could also be referencing a TCP or UDP port number; or Serial and Parallel ports.
Please check the following section of the FreeBSD handbook:
(Yes, a bit RTFM, but the Handbook is really, really good)