There ARE antique poker chips with a cow engraved on them, but I think most of the references to 'cow chip', even in the collector community refer to exactly what was defined in the earlier thread.

By the way, there are also owl engraved poker chips, but most references you will see in the hobby are to one of the several Owl Club casinos that operated in Nevada.

To close with still more confusion, there was a casino here in Oregon run by the Cow Creek Tribe of indians. They have since changed the name of the place to Seven Feathers, but here's the original and current versions of their chips look like. These would be creek-bed cow chips, I guess (very sloppy).