This is the 9890th most frequent German word.
obenauf
"Obenauf" means "on top" or "at the top" in English.
In this sentence, 'obenauf' means 'on top,' describing the position of the book on the stack.
Das Buch lag obenauf dem Stapel.
The book was on top of the stack.
Here, 'obenauf' is used figuratively, meaning someone feels dominant or victorious.
Nach seinem Sieg fühlte er sich obenauf.
After his victory, he felt on top of the world.
'Obenauf' in this sentence indicates placement, signifying 'on top' in a spatial context.