screwbean a bean from the plant Prosopis juliflora, which is a shrub related to mesquite and which grows in the south-western USA. It is also called tornillo, screws, and screw pod mesquite, all its names having reference to the spiral seed pods. The pods are rich in sugar. The beans may be ground and then combined with water to produce a nourishing gruel. The Mojave Indians thought that the taste of young screwbeans was unsatisfactory and used to leave them to decay in a pit lined with arrow weeds for about four weeks, after which they would dry and grind the beans and then make the gruel.