an·​nex·​in | \ ə-ˈnek-sən How to pronounce annexin (audio) \
plural annexins

Definition of annexin

: 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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First Known Use of annexin

1987, in the meaning defined above

History and Etymology for annexin

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

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The first known use of annexin was in 1987

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readily or continually undergoing change

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