1 definition by quirkygirl

noun. The name of the unique language that develops over time between siblings. Oftentimes outsiders will be able to listen to a conversation between siblings and have no idea what was said.
The twins spoke Demalish so fluently that even their parents did not understand that they were plotting an epic prank even though the plotting took place at the dinner table.
by quirkygirl March 24, 2011
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