a cymose inflorescence characteristic of some angiospermous plants. The main axis of a polychasium has more than two secondary axes below the apical flower, which grow longer than the main axis and end in flowers that bloom later. Some botanists make a distinction between polychasium (for example, in some Ranunculus), in which only secondary axes depart from the main axis, and a compound polychasium (for example, in elder and spurge), in which several tertiary axes depart from each secondary axis.