A sign of derision made by putting your thumb on your nose and wiggling your fingers. Original motion created by placing ones thumb upon the side of their nose and pushing out as if giving thumbs up. Guaranteed to offend soccer moms and yuppie pigs.
Etymology: Originated in the 1640's in Vienna. Gained popularity when Shakespeare is said to have 'thumbed his nose' at Edmond Rostand.
Debbie asked Joe, "Did you just thumb your nose at me?"