keitai banshee 

A young uncouth Japanese woman (often a Kogal/ganguro type) who screams into her mobile phone (known as a keitai in Japan) while in public - especially on trains or in restaurants.

Keitai - mobile phone
Banshee - a mythical woman who kills by screaming in such a high pitch that it breaks glass and the arteries of its victim's body so that they drown in their own blood.

"If that keitai banshee at the end of this carriage doesnt shut up in a moment, I am going to plant my foot in her ass"

"I am so tempted to grab that keitai banshee's phone and snap it in half"

keitai banshee by Kraken December 29, 2007