McShift 

1) A 16 hour shift at McDonald's or some other second rate, crap job. aka. a double shift
2) One who behaves like a total dickhead.
3) A girl who stands you up for a date.

1) I am tired as hell. I just worked a total McShift.
2) Ben! Stop being a McShift.
3) Nancy Jean didn't show up for our date. I've been completely McShifted.

McShift by aarondawg August 3, 2005

M-Shift 

The abbreviation of the phrase Mental Shift.

An M-Shift, or mental shift, is a therianthrope-related occurence wherein a therian feels their mindset, or current mentality, becomes that of their phenotype, or animal.

An M-Shift may be brought upon by many environmental and/or sensory factors, such as weather, certain people, smell, sound, taste, etc.

How intensely an m-shift is felt, and how long they last, vary from therian to therian.

See also: P-Shift, Astral Shift, Suntherian Shift, and Phantom Limbs.

I had an M-Shift about a week back; my first in quite some time.

M-Shift by Winter Paws January 20, 2007

McShifting 

Rapidly pressing shift on minecraft to simulate a sexual action. Sometimes in the real world known as "humping."

Jordan and Sean hopped on the bed and started to Mcshift. Ethan later that day asked us if we did because he heard us McShifting.

McShifting by scousecraft2 July 19, 2012

M-Shift 

Short for "mental shift." This is a term therianthropes and otherkin who wish to make excuses for their sometimes bizarre and animalistic behavior use to avoid taking responsibility for their actions; they believe that by claiming that they've "mentally shifted" into their spirit's supposed true form that they should receive pity no matter what they do.

I didn't mean to go on a murderous rampage on the full moon. Please excuse me: I m-shifted into a werewolf mentality and I couldn't help myself!

M-Shift by Puffing Tom July 14, 2010