neta
"La neta" is the truth, or what you say when you're about to be honest, like "to be honest". "Neta" on its own is like "for real", and if you ask "¿neta?" you want to know if something is true.
La neta no me gustó la peli. —¿Neta? A mí me encantó.
"La neta" I didn't like the movie. —"¿Neta?" I loved it.