When your mother gives you a dumbass reason for something.
For example:

Jack: My mum told me to get a job last week so I got a paperound. When I got home one night from it she had a go at me and told me I can't do a paperound.
Matt: Why?
Jack: Because 'She's my parent and I must bow to her every ass-faced command'
Matt: Sounds like Mum Logic to me.
by RawrAthon September 19, 2009
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