dechristmasizing
The process of taking down all the Christmas decorations after Christmas is over.
I have the major chore of dechristmasizing the house until next year when it gets christmasized again.
dechristmasing
The process of removing all Christmas decorations from your house, Christmas tree, etc. It is usually a long process, often done the day after Christmas.
"Hey Mike what are you doing on your ladder?"
"I'm dechristmasing the top of my house!"
"I'm dechristmasing the top of my house!"
Dechristmased
To remove all signs of holiday cheer from your home and get back to "reality."
I spent all day yesterday and dechristmased the house