Around the middle of chapter 9 of I Will Fear No Evil, while still recovering from surgery, Eunice is relaxing to some music: "For an hour and more she listened to a tape of evergreens, from classic rock she had never grown used to clear back to folk music popular before Johann Schmidt was born."

It seemed to me when I came across this passage that perhaps no one had ever used the term "classic rock" before then, at least in print.

Was Heinlein the first to imagine that there'd be such a thing as classic rock?

Opinions? Facts? Both are welcome.

That's a good catch, and ca. 1970 I'd bet there are very, very few prior examples of the phrase. I think Heinlein might have been "making strange" and been completely blindsided by reality.

That is a good catch. I did not hear "classic rock" on the airwaves until the early nineties.

What Peter said. I think I first heard the term in the early '90s as well. I never listened to much rock, so I wasn't paying attention, but that sounds right.

Thanks for the research. Several of these instances do seem to use classic rock in the sense used in the novel - i.e., as a genre. Perhaps Heinlein was the first to use the term in fiction?

To be fair, the same ngrams chart shows that the usage increased dramatically starting 1988.

I first heard/started using "classic rock" when I was just entering my 20s at the start of the Brit "invasion." [I turned 21 just in time for the 1964 elections].

[How little we knew how deeply those Brit rockers we were denigrating were steeped in '50s rock and roll as well as blues, jazz, etc. Sigh. How did I survive my 20s?!?!?!]

I'm betting Heinlein was more a fan of "classic ragtime."
That's very cool that you picked up on the "classic rock" reference in IWFNE. As with many things in Heinlein's writings, he seemed eerily ahead of his time - particularly on cultural issues.