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1.
When one must always respond to said persons mother with the words: yes mommy, mom, or mother. This is usually the result of heavy parenting and overly obedient children. Every Yes mummer is physically and mentally incapable of uttering the word no to their or any persons mother. The yes mommer is looked down upon by the group, usually because of their forced early departure time, normally around 8:45pm.
John: Sorry guys, my mom's being a bitch and is making me go home early.

Group: BULL SHIT

Martin: Yeah right, you just can't say no to your MOMMY you yes mommer.
by SK AC November 12, 2011