Main Entry: aphe·re·sis

Pronunciation: \ˌa-fə-ˈrē-səs\

Function: noun, plural

Inflected Form(s): aphe·re·ses \-ˌsēz\

Etymology: from -apheresis (as in plasmapheresis)

Date: 1977

: withdrawal of blood from a donor's body, removal of one or more blood components (as plasma, platelets, or white blood cells), and transfusion of the remaining blood back into the donor —called also pheresis