A cull dairy cow is a cow that has been selected to be separated from the main herd and sold because she is a poorer milk producer than desired, has chronic lameness, too old, bad teeth, etc.
She can be anywhere from two years of age to 20. It all depends on when the producer decides to cull his cows and what his/her criteria is/are for culling them.
A cull cow. She can also be called a free-loader, a barren cow, an old cow, etc., but cull cow is the best term to use because cows that can no longer have a calf is one that no longer needs to be a part of the more productive cow-herd.
A cow. Or, if you want to go into specifics, a dairy cow.
It gives more milk than what it would normally produce for its calf. That's what constitutes a cow for being a dairy cow.
The dairy cow.
Dairy
That all depends on the breed. Are you asking about a dairy cow or a beef cow, and what breed of dairy or beef cow?
Dairy cattle like Holsteins, Brown Swiss and Jerseys.
A dairy cow would die a matter of a few weeks before she even gets to the point where she is deemed "feral." I would see a beef cow becoming feral, yes, but not a dairy cow.
A farm
There's not really an answer... You just call it a cow...
cow