noun an·nex·in \ə-ˈnek-sən\

Definition of annexin



  1. :  any of a family of proteins found in eukaryotes (such as mammals, birds, and plants) that bind to phospholipids in the presence of calcium —often followed by a number usually expressed in Roman numerals to indicate type Annexin V may play significant roles in cell physiology, including such processes as control of membrane permeability to calcium … — William H. Strauss et al., Lancet, 15 July 2001

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Origin and Etymology of annexin

blend of 1annex and synexin, earlier name for an adrenal medullary protein with the properties of annexin

First Known Use: 1987

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