[ kahy-nin, kin-in ]
/ ˈkaɪ nɪn, ˈkɪn ɪn /
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noun Biochemistry.

any of a group of hormones, formed in body tissues, that cause dilation of blood vessels and influence capillary permeability.



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Origin of kinin

1950–55; independent use of -kinin, or (cyto)kin(esis) + -in2

Definition for kinin (2 of 2)


a combining form used in the names of hormones, especially peptide hormones: bradykinin; cytokinin.

Origin of -kinin

<Greek kīn(eîn) to move, set in motion (cf. kinesis, kinetic) + -in2
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

British Dictionary definitions for kinin

/ (ˈkaɪnɪn) /


any of a group of polypeptides in the blood that cause dilation of the blood vessels and make smooth muscles contract
another name for cytokinin

Word Origin for kinin

C20: from Greek kin (ēma) motion + -in
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medical definitions for kinin

[ kīnĭn ]


Any of various polypeptides, such as bradykinin, that act locally to induce vasodilation and contraction of smooth muscle.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.