Rūpa-Kalāpa
rūpa-kalāpa：'corporeal group'，material unit，designates a combination of several physical phenomena constituting a temporary unity．Thus，for instance，the so-called 'dead matter' forms the most primitive group，consisting only of 8 physical phenomena，called the 'pure eightfold unit' or 'octad' （suddhaṭṭhakakalāpa），to wit：the 4 elements （the solid，fluid，heat，motion）； colour，smell，taste，nutriment （paṭhavī，āpo，tejo，vāyo； vaṇṇa，gandha，rasa，ojā）．In Vis．M．，and elsewhere，it is also called ojatthamaka-kalāpa，'the octad with nutriment as the 8th factor'．
The simplest form of living matter is the '9-fold vitality unit' or 'life-ennead' （jīvita-navaka-kalāpa），formed by adding 'vitality' to the octad．Seven decades，or units of ten （dasaka-kalāpa），are formed by adding to the 9-fold unit one of the following corporeal phenomena：heart （physical seat of mind），sex，eye，ear，nose，tongue or body．- See Vis．M．XVIII，4； Compendium of Buddhist Philosophy （PTS），p．164，250； Aṭṭhasālinī Tr．，II，413f．