An M Card is short for a Medicinal Marijuana Registry Card. When you have one you are a part of the MMRC, the Medicinal Marijuana Registry Club.

Here's the legalities for the state of Colorado:

Amendment 20 authorizes a patient or a primary caregiver who has been issued a Medical Marijuana Registry identification card to possess no more than two ounces of a usable form of marijuana and not more than six marijuana plants, with three or fewer being mature, flowering plants that are producing a usable form of marijuana.
My snowboarder bro was just issued his M Card. He's a part of the MMRC now and has the best strains in town!

Did you hear, Oliver's Dad just got his M Card, he has cancer, its really sad, but at least he feels good about life because he's a part of the MMRC.

Having an M Card means you are allowed to enjoy all the benefits that marijuana has to offer and partake in the cultivation of your own plants if you so choose.... under the right legal circumstance, of course.

I wonder if Bill Maher has his M Card?

Why do we even need to have an M Card to enjoy a naturally occurring plant? That should be an inherent human right, it is ours just as much as anyone's.

Honey is a progressive, politically active person here to educate people on the M Card, ask her if you have any questions, she's really sweet.
by RandiWordHead June 7, 2009
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M card: The "Menopause" card.

Menopause; the menstrual cycle (periods) ceases for life. No longer able to procreate. Usually occurs between mid-to-late-40's. Sexual freedom; pregnancy is no longer a concern.
I hold my M card, my daughter still holds her V card - or the virginity card.
by MsRose1 November 18, 2010
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A permit or pass combined with an image which allows the person you give it too to masturbate. In order for the M card to be valid, one must send an image with a caption or any other indication that the image you sent is indeed, “ok to nut to”
I sent my gf an M card with a picture of Ben Swole on May 4th. Nonetheless the nut is strong with this one
by OT14 May 5, 2021
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