I remember reading the lyrics for this song in a syndicated column the local newspaper when the song came out in 1971 (about 45 years ago as I write this) I was starting 11th grade, and I was 15.
The story explained that it was “actor out on loan” and it explained the meaning of the term, which is somewhat literal, I believe. But I’ve never heard anyone use the term in real life.
I didn’t understand the metaphors then, but this is The Doors and they were stoned or drug-addled, I guess. No need to overthink it (it’s vague and it’s not Shakespeare) but…
“Dog without a bone”...maybe it means he has no purpose or job and could be happier than he is. Or maybe it’s a play on “like a dog with a bone” (relentless). Or maybe it’s like a puppy that has no chew-toy and starts being destructive and chewing on furniture.
I’m not sure now of the meaning of “actor out on loan”, but I think it means the actor isn’t wanted for a good role, and is being shunted aside to work in some crummy role, perhaps as an extra, somewhere else, for another production company. Maybe this is why he’s on the road: he’s hitchhiking to a movie set. (I tend to take things literally, except for the squirming toad part.)
Being an actor out on loan is apparently not a good thing, but I could make an argument that it’s better than not working at all.
It’s great music, though: the rain sound effects, the sense and rhythm of driving down the road, Jim Morrison’s vocals, the harp-like sound of the keyboards…
There was another group, Kraftwerk, that made a somewhat longish tune called “Autobahn” (the German word for their high-speed expressway) a few years later, but it’s an entirely different mood and genre, more electronic, that possibly foreshadowed the Europop of the early ‘80’s.
Sorry for the digression; I prefer Riders on the Storm. It’s kind of like comparing apples and oranges. But I’m old now, you know, so I ramble.