When a person acts in a rediculous and inexplainable manner, often followed by a rediculous laugh that sounds like a small animal taking it's last gasps of breath.
Rachael acts like such a flange!!

Rach you have Flange Behaviour in the evenings!

Rach, cut out the Flange Behaviour please. you fucking flange!
by tommyseal January 25, 2012
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