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second messenger

noun Biochemistry.
  1. 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.
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. 2018
second messenger in Culture

second messenger

A molecule that relays messages in a cell from a receptor on a cell membrane to the final destination where an action within the cell is to take place. (See signal transduction pathway.)

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.