A flat white (type of coffee).
A flat marinated cut of meat.
a chicken flattie
A flat store.
A flat-bottomed sloop-rigged sharpie.
A flattie spider.
A traditional two-dimensional motion picture, as opposed to a deepie.
A flatfish.
A flathead (fish).
A flat tire/tyre.
A policeman.
A flathead V8 engine.
A hot rod fitted with a flathead V8 engine.