second messenger: meaning, definition, pronunciation and examples
C1technical / academic
Quick answer
What does “second messenger” mean?
In biochemistry and cell biology, a molecule that relays signals from a receptor on the cell surface to target molecules inside the cell.
Audio
Pronunciation
Definition
Meaning and Definition
In biochemistry and cell biology, a molecule that relays signals from a receptor on the cell surface to target molecules inside the cell.
In a broader metaphorical or business context, it can refer to a secondary agent, medium, or communication channel that transmits information, instructions, or influence from a primary source to an intended target.
Dialectal Variation
British vs American Usage
Differences
No significant lexical or conceptual differences. Spelling conventions follow standard UK/US patterns for component words (e.g., behaviour/behavior in related texts).
Connotations
Identical technical connotations. Metaphorical use is equally rare in both varieties.
Frequency
Virtually identical, confined to biology, medicine, and pharmacology texts.
Grammar
How to Use “second messenger” in a Sentence
[Noun Phrase] acts as a second messenger for [Signal][Signal] triggers the release/production of a second messengerThe second messenger [Verb Phrase, e.g., activates kinases, diffuses through the cytoplasm]Vocabulary
Collocations
Examples
Examples of “second messenger” in a Sentence
verb
British English
- The hormone doesn't enter the cell; it functions by second-messengering its signal via cAMP. (Note: highly non-standard, illustrative only)
American English
- The signal is second-messengered through the production of inositol trisphosphate. (Note: highly non-standard, illustrative only)
adverb
British English
- The signal was transmitted second-messenger-wise. (Note: extremely rare and contrived)
American English
- The cell communicated second-messenger-style. (Note: extremely rare and contrived)
adjective
British English
- The second-messenger hypothesis was revolutionary. (attributive use of noun compound)
- The second messenger response was rapid.
American English
- Researchers mapped the second-messenger cascade. (attributive use of noun compound)
- Second messenger systems are a key topic.
Usage
Meaning in Context
Business
Rare; metaphorically for a subordinate who communicates a superior's directive. 'The CEO didn't email herself; she used her PA as a second messenger.'
Academic
Primary domain. Standard term in biology, physiology, and pharmacology journals. 'The study focused on cAMP's role as a second messenger in hormone action.'
Everyday
Extremely rare. Would likely cause confusion if used outside a scientific conversation.
Technical
Core, precise term. Refers to specific molecules like cAMP, cGMP, IP3, DAG, calcium ions (Ca2+).
Vocabulary
Synonyms of “second messenger”
Strong
Neutral
Weak
Vocabulary
Antonyms of “second messenger”
Watch out
Common Mistakes When Using “second messenger”
- Using 'secondary messenger' (less common but not incorrect).
- Treating it as an adjective-noun pair instead of a fixed compound noun (e.g., 'a messenger that is second').
- Confusing it with the 'first messenger' (the extracellular signalling molecule like a hormone).
FAQ
Frequently Asked Questions
No, it is a highly specialised term primarily used in biology, medicine, and pharmacology. Its use in everyday conversation would be very unusual.
Common examples include cyclic adenosine monophosphate (cAMP), cyclic guanosine monophosphate (cGMP), inositol trisphosphate (IP3), diacylglycerol (DAG), and calcium ions (Ca²⁺).
Yes, but it is rare. It can metaphorically describe a person or system that conveys a message or instruction from a primary authority to a final target, emphasising the indirect, relaying nature of the communication.
The first messenger (e.g., a hormone or neurotransmitter) is the extracellular signalling molecule that binds to a receptor on the cell surface. The second messenger is the intracellular molecule whose concentration changes in response to this binding, carrying the signal forward inside the cell.
In biochemistry and cell biology, a molecule that relays signals from a receptor on the cell surface to target molecules inside the cell.
Second messenger is usually technical / academic in register.
Second messenger: in British English it is pronounced /ˌsek.ənd ˈmes.ɪn.dʒər/, and in American English it is pronounced /ˌsek.ənd ˈmes.ən.dʒɚ/. Tap the audio buttons above to hear it.
Phrases
Idioms & Phrases
- “None specific to this term.”
Learning
Memory Aids
Mnemonic
Think of a military chain of command: the General (first messenger/hormone) sends an order to the Captain (receptor), who then tells the Sergeants (second messengers) to mobilize the troops (cellular response).
Conceptual Metaphor
COMMUNICATION IS A RELAY RACE (the first runner passes the baton to the second). / A MESSAGE REQUIRES A COURIER (the primary sender employs a secondary courier for the final delivery).
Practice
Quiz
What is the primary function of a 'second messenger' in biochemistry?