Synedoche

that’s the word for using Coke for soft drinks and Xerox for copiers and copies.

It is using the word for part of something for the whole. Ex. How do you like my new wheels? I need a kleenex. Pay for it with your plastic.

The word is actually synecdoche, as in the 2008 Charlie Kaufmann movie Synecdoche, New York (which is where I first came across the word.)

Is there a convenient word for “what column does any of this have to do with?”

Not the OP, but I assume this line:

“Later, by means of the metaphoric process called synecdoche, taking the part for the whole, the Franks applied the name to all the German-speaking tribes, and thus we have Allemagne.”

from Why are there so many names for Germany, AKA Deutschland, Allemagne, etc.?

I was aware of this meaning of “synecdoche” (as in “Get your ass over here!”). I wasn’t aware that the term “synecdoche” also applied to genericized trademarks (like “Xerox” for copier or “Band-Aid” for bandage), but Wikipedia seems to agree that it does.

In Randall Garrett’s Lord Darcy stories of sorcery and detection, the magical Law of Synecdoche states The Part is equivalent to the Whole.

I note that there is no reference quoted for that assertion by Wikipedia. It does not to me seem that saying, “I’m going to Xerox it for you” is a form of synecdoche, because I’m not using part of something to describe the whole. But I’m not an English expert, so I could be wrong. But I think we can demand something more authoritative than an uncited claim in Wikipedia.

Is this meant in the sense of a ‘Xerox’ being equivalent to a ‘Xerox copy’, or ‘Band-Aid’ being equivalent to ‘Band-Aid bandage’? So the brand names are used as part of the full name of the product?

I share your skepticism that genericized trademarks are synecdoche.

The Wikipedia article on generic trademarks notes a nice term that I hadn’t come across before - “genericide”.

I assume the OP is referencing this article:

Is there a term for “trade names that become generic”?

The term “genericide” is mentioned in that article (which dates to January 2000).

I would like to point out one error in Cecil’s column. “Aspirin” is still a registered TM and generic tables are called ASA in Canada and presumably everywhere outside the US. In the US, the name was seized as an alien property during WW II and put into the public domain. There must have been a number of such seizures but the only one I am aware of is the copyright on van der Warden’s algebra book, quite popular (for graduate courses) when I was a student.

It looks like a number of other countries have gone the same way as the U.S.

I didn’t realize that it was still a trademark in much of the world.