wedge

A.k.a. warikomi. A proponent move played to invade the centre of an opponent position. For example, in fuseki, a move played on the third line with miai extension to either side so as to occupy side territory between two corners dominated by the opponent stones. In the diagram if Black should approach white 1, either from the top or here from the more likely direction of below, the two skip to A or B would be sufficient to settle the white stones.