Copy of a Hellenistic Aphrodite Kallipygos at The Hermitage in St. Petersburg.
Here's your word for the day: Anásyrma - the gesture of lifting up the skirt or kilt.
Anasyrma differs from flashing, a physically similar gesture as an act of exhibitionism, in that an exhibitionist has an implied purpose of his/her own sexual arousal, while anasyrma is only done for the effect on the onlookers.Photo credit Yair Haklai.
Anasyrma may be a deliberately provocative self-exposing of one's naked genitals and/or buttocks. The famous example of the latter case is Aphrodite Kallipygos ("Aphrodite of the beautiful buttocks"). In many traditions this gesture also has an apotropaic character, as a mockery towards a supernatural enemy analogous to mooning.