A Japanese facial gesture, usually considered childish. It consists of an eyelid pull while sticking the tongue out. It is sometimes accompanied by the sound べえだ (beeda, pronounced "behhh-dah"). This gesture is also done in France and Québec, where it is accompanied by saying "mon oeil" ("my eye").
The gist of the the gesture is an infantile taunt - the Japanese equivalent of thumbing your nose at someone, and/or yelling "Nyah nyah nyah" or "Neener neener" or the like.