[kahy-nin, kin-in]

noun Biochemistry.

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

Origin of kinin

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


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 Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for kinin



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

Medicine definitions for kinin




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.