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An adjective used to describe someone who always seems to assume things.
Adam: Christy thought you and Heather broke up because she saw you getting pizza with another girl.

Jake: I hope she didnt say anything to Heather because that was just my sister.

Adam: Jeez, Christy has to stop being so assumptuitive.
by Stephers_0o7 August 17, 2008
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