The G-rated, family friendly term used to define the usual "Holy Shit" moments, i.e. getting a super wet smooch, tripping over thin air and arguing with uptight parents.
"Holy Smacks mom, I'm 25!"

or

"Holy smacks! That wasn't there before!"

Gasping after running a marathon: "Holy smaaaaacks!"
by That's some bad hat harry April 23, 2011
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