You intrigued me with this one as I was told once, quick Google reveals this;
"HOOAH is one of the most widely used military acronyms of all times, and no one can agree on its spelling, origin or even on its meaning for that matter. What exactly does it mean? Heck, is it even an acronym at all?
I have scoured the Internet, referenced books, and asked military scholars. Only one conclusion has become of my research: There is no known origin for the meaning of hooah; many have opinions but there is no single theory"
"Personally, when I went through Basic Training, I was taught the acronym HUA stood for I hear you, I understand you, and I acknowledge your statement."
This is what I was told.
But then rather oddly states;
"Urbandictionary.com claims the term hooah was originally used by the British in the late 1800's in Afghanistan; then, more recently adopted by the United States Army to indicate an affirmative or a pleased response."
What does one think to that?
No I won't include the links, you can Google can't you?