When a girl has to sneeze after you've unloaded in her mouth while holding her hand in front, resulting in the jizz coming out through her nose.

Originated as a variation on snowballing.
Jay: Yo, Frizzle's girl had a nose avalanche yesterday, she was all allergic and had to sneeze.

Lawrence: Rly? Trippin' balls.
by The_Jay March 4, 2010
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