Figurative language
ROCK BOTTOM: At very bottom. Like the rocks at the bottom of a river?
I assumed it was from digging: you give up with the spade when you hit rock bottom and can't go any lower.
psi
That sounds like a better explanation.
ROCK BOTTOM: At very bottom. Like the rocks at the bottom of a river?
I assumed it was from digging: you give up with the spade when you hit rock bottom and can't go any lower.
psi
That sounds like a better explanation.