(katakana: ビーデー , romaji: bi-de-
One of the standard buttons on the veritable Captain Picard's console attached to every Futuristic Japanese Super-Toilet.
The standard icon is of a lady (distinguishable by her triangular skirt, pigtails, lack of legs, and pink colour) suspended above the astrological symbol for Aries. Behold:
; : ;
I wouldn't know what the button does, because I have never, ever, pushed it.