Merriam-Webster's Collegiate® Dictionary, 11th Edition
ASIDE
I. adverb
Date: 14th century
to or toward the side , away from others or into privacy , out of the way especially for future use ; away , away from one's thought or consideration ,
II. preposition
Date: 1592
beyond , past ,
III. noun
Date: circa 1751
an utterance meant to be inaudible to someone, a straying from the theme ; digression