I too have never heard of the term "finals" in aviation.
You can always tell the non aviation people when they use that term. Jetskipper refers to a different sort of "finals." I have heard the term as "the numbers."
The one thing that I have never liked was the term "rudders." On every aircraft I have ever flown there have always been just ONE RUDDER!
Maybe the confusion is the 2 rudder pedals, but I always chastize pilots when I hear them say rudders as it is just plain wrong.
"You Can't Beat The Experience"