HELLO, is it? Hollo! Hallo! Halloo! is what your ancient Old High German/Old French predecessor did shout, bellow, exclaim, roar. A loud cry to call attention: quarry spotted, trespasser warned, ferryman hailed, objection exclaimed, greeting chorused, champion exhorted! These days, it is tamed to the decorus emollient of everyday encounter…but still we sometimes holler.
Etymological illuminations brought to you by Jane