A Japanese word which describes the traditional formal way of sitting (literally "correct sitting") in that country.
To sit seiza-style, one first kneels on the floor, and then rests the buttocks on the heels, with the tops of the feet flat on the floor. The hands are sometimes folded modestly in the lap and sometimes placed palm down on the upper thighs with the fingers close together. The back is kept straight, though not unnaturally stiff. Traditionally, women sit with the knees together while men separate them slightly, proportional to body size. Some martial arts, notably kendo and iaido, may prescribe up to two fist widths of distance between the knees. The big toes may rest side by side or are sometimes overlapped.
Some find it painful to sit in seiza, bit I am superman, and hence feel no pain!