The verb “renverser” means ‘to knock over, to knock down, to overturn…”
But we use the participe présent “renversant” to say ‘amazing, staggering’.
Cette nouvelle est renversante: This news is unbelievable.
Viens voir, c’est renversant! have a look, it is amazing!
Because of its meaning, we also use it in a funny way for things that are down or knocked down.
When someone falls: c’est renversant!
When a thing is upside down: c’est renversant!