Contraction of Immature and Childish to further recognize and magnify how immature and childish you think that someone is. It's the line where immature and childish go from being funny to being absolutely stupid!!
James was depantsing people at school today and it was hilarious until he did it to the principal and got all of us in trouble with his immachildish ways.
by BigTone June 22, 2010
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