any of various intracellular chemical substances, as cyclic AMP, that transmit and amplify the messages delivered by a first messenger to specific receptors on the cell surface.
Malpractice, Malarkey, And Other Words From The Second Democratic DebateHere's our roundup of top terms that created buzz on Dictionary.com during the second Democratic debate. For the first five words, we can thank the 10 candidates from the first night of the debate on July 30, and for the second five, the remaining 10 debating on July 31.
Compare first messenger.
Origin of second messenger
First recorded in 1960–65
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Culture definitions for second messenger
The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.