Bulk density The mass of many particles of the material divided by the total volume they occupy. The total volume includes particle volume, inter-particle void volume and internal pore volume. Originally from the CUAHSI HIS VariableNameCV. See: http://his.cuahsi.org/mastercvreg/edit_cv11.aspx?tbl=VariableNameCV. ODM2 Variable Name Controlled Vocabulary ODM2 Working Group A vocabulary for describing the name of Variables.