When I was little, I thought the Christmas song said, "Deck the halls with BALLS of holly."

Well, the berries ARE like little balls, you know.

There's been a bug going around

 

When I was little, I'd hear my parents talk during flu season about the bug that was currently going around, and I thought they meant, you know, a BUG. 

Treat it with kid gloves

 

When I was little, when grownups talked about "kid gloves" I thought they meant the gloves kids like me wore to play cowboys. 

Taking things for granite

 

When I was little, when the grownups said "taking things for granted" I thought they were saying "taking things for granite."