Meaning 1:

A person who works in the railway corridor, accepting that while this is better than mining it comes at a similar social price, which is justified for a small financial gain, and still not on par with a poorly paid CPA.

It’s unlikely to see this person on a weekend, you will often hear them complaining that there S/O is mad at them for never been home.

Meaning 2:

An insult used by common folk not understanding why there could possibly be 50+ people doing nothing on the railway at the same time, usually the source of blame as to why their Monday morning train is 5 minutes late.
Meaning 1:

Derik: Is Peter coming out this weekend with the boys ?

John: Nah mate, Pete’s a raildog now.

Meaning 2:

Person drives past a group of workers standing inside a railway fence doing nothing:

‘ you fucking raildogs! ‘
by The Camel June 6, 2022
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