It's an acronym for "Heard, Understood, Acknowledged" HUA, phonetically sounds like "Hooah" and I'm proud to say my first instinct was to shake my head in disappointment every time it was uttered because it sounds so STUPID. Literally got an 'atta boy' after being yelled at by a MTI for visibly shaking my head in disapproval, he ripped me a new one and asked WTF my problem was? I replied, "I am not a fucking cheerleader Sergeant!".He loved my response, turns out I was in good company.