Heads up

This phrase is American in origin and use and is rarely used outside of the nation and its people. It's used in the form of a warning, almost like the word "four" is yelled when a golf ball goes rogue. A second use is in the form of leadership - at the head of the whole organization or "heads up the whole organization." And a final popular use for the phrase is centered around emotion - when someone is down due to losing or whatever we will say "Hey, heads up - it's not over yet" or something similar. (source)