I said TGIF to my wife last week. She said, "TGIF? What does that mean?" I told her it depends on context.
If you hear it at work, it means, Thank God It's Friday.
If you see it on a pair of shoes, it means, Toes Go In First.
If I say it to you, it means, Tits Go In Face!

She laughed and flashed 'em at me. Wish I had the camera ready!