1. The objects (clothes, trash, make up, etc) your aunt leaves around the house when she is staying with you. This can also be used to describe the mess that is left after her stay.

2. The nonsensical things your aunt says that matter none.
1. Aunt: I can't seem to find my tooth brush.

You: It's in the restroom, along with the left of the auntimatter you left behind.

2. You: I'm so tired of listening to her auntimatter. I feel like I'm talking to a fortune cookie.

Friend: Just don't try to crack her open to find your lucky numbers.
by mandersplatwood March 6, 2011
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