apheresis

From Latin aphaeresis, from Ancient Greek ἀφαίρεσις (aphaíresis, “a taking away”), from ἀφαιρέω (aphairéō) (from ἀφ- (aph-), variant of ἀπό (apó, “off, away from”) before an aspirated vowel) + αἱρέω (hairéō, “to take; to snatch”)) + -σις (-sis, suffix forming nouns of action); the grammatical sense developed in Latin.