Calendarman 

The freaking greatest Super villain in all of DC universe. He is over weight, bald, and greasy. Enjoys doing things on special days like Christmas. Has the special ability to know what day it is without looking at calendar. Doesn't really have any powers but can tell what day it is better than almost anyone.

Robin : Holy Spirit Batman all the villains have escaped
Batman : What about Calendarman?

Robin : No, it's not a holiday yet.

Calendarman by Calendarman!! November 22, 2011

Calendar Man

To be messed up and have a disordered life. Not having a path in life and ambitions as well as goals. Refers to needing a calendar to sort out one's life.

Chloe: " Michelle you're so awesome and better than me! I don't know what I want to do with my life!"
Michelle: " Ahh gyal dem you's a calendar man."

Calendar Man by michelledomination March 3, 2016

Calendaring 

To do what a calendar does; to calendar. Calendaring is the verb form of the noun, calendar. When you are calendaring, you are interacting with a calendar in some way.

"Suzie, put that phone down this instant!"
"But grandma, I was just calendaring! Your birthday is coming up, and I didn't want to forget."

Calendaring by Marc IRL December 15, 2011