There’s a “fuck” in Fleetwood Mac’s “The Chain”. It happens in the first second or so, as someone is moving around a bit, well before the first beat of the song. You have to turn the volume up pretty loud to hear it, and then you’ll want to turn it down again before the music starts.
This one is fairly well-known, but at the very end of the Doors’ song “Touch Me,” over the final musical measure, you can hear Jim Morrison say, “stronger than dirt.”
That phrase was the tagline for Ajax, a brand of household cleaner. Stories vary as to whether it was (a) just a silly Easter egg-style joke on Morrison’s part, or (b) the band had been approached by advertisers who wanted to use their music in ads (which Morrison was opposed to), and he inserted the tagline as a statement about their music being used commercially, or (c) that his bandmates were actually considering selling the rights to their songs to advertisers, which had angered Morrison, and he inserted the line for similar reasons to (b).
I’ve never seen this confirmed but… The fourth Roxy Music album is called Country Life. Shakespeare used that pun.
Here’s a link to the cover - probably NSFW, so I’ll spoiler it:
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