unreasonableness; perverseness; obstinacy
Almost always used in the set phrase 横車を押す, meaning to push through something unreasonable or forcibly have one's own way. The image is of pushing a cart from the side instead of from behind, making it difficult to move properly.
See also: 横車を押す
He pushed through his own plan unreasonably at the meeting.
side wheel throw (judo)
A judo technique where the opponent is thrown by twisting them sideways over the hip. A specialized term used in martial arts contexts.
Yokoguruma is one of the throwing techniques in judo.
Compound of 横 (side) and 車 (wheel/cart). The idiomatic sense comes from the image of pushing a cart sideways, which is an unreasonable way to move it.