An exclamated expression used to comment on women’s
breasts. (Ace meaning 'excellent,' racking meaning '
breasts'). Can also be used, oddly enough, for anything that is good. This expression developed in Oyster
Bay.
'
Dude, check out that acerack on that girl!'
'
Dude, this band is surprisingly acerack.'
'My
hat is like, totally acerack.'