Caesalpinia bonduc, commonly known as Gray Nicker, is a species of flowering plant in the senna family, Caesalpiniaceae, that has a pantropical distribution. It is a vine-like shrub that reaches a length of 6m (20ft) and scrambles over other vegetation. Stems are covered in curved spines. Its 2cm (0.79in) gray seeds, known as nickernuts, are buoyant and durable enough to be dispersed by ocean currents.