synapses

A student learns about synapses in a biology textbook.

Definition

1. Noun (plural; singular: ):
   • Neurobiological structure: "synapses" are the microscopic junctions between two nerve cells (neurons) where electrical or chemical signals are transmitted from one neuron to another. They are essential for communication within the nervous system.
   • Cytological term (rare): In cell biology, "synapses" can refer to the pairing of homologous chromosomes during meiosis (a stage of cell division), though this usage is now largely replaced by "synapsis."

Usage Examples

• (The structural connections that allow neural communication.)
• (The junctions that adapt with experience.)
• (The connections created and eliminated in the brain.)

Advanced Usage

• "synaptic plasticity": the ability of synapses to strengthen or weaken over time, which underlies learning and memory.

  • Long-term potentiation is a form of synaptic plasticity that strengthens synapses. (The process of making neural connections more efficient.)

• "synaptic cleft": the tiny gap between the presynaptic and postsynaptic neurons across which neurotransmitters diffuse.

  • Neurotransmitters are released into the synaptic cleft to bind to receptors. (The space where chemical signals travel.)

Variants and Related Words

• Synapse (n, singular): a single junction between two neurons.

  • Each synapse can be excitatory or inhibitory. (A single connection.)

• Synaptic (adj): relating to or involving a synapse.

  • Synaptic transmission is the process of signal transfer across a synapse. (Pertaining to the junction.)

• Synaptogenesis (n): the formation of new synapses.

  • Synaptogenesis is crucial during early brain development. (The creation of neural connections.)

Synonyms

• Neural junction: a general term for the connection point between neurons.
• Neuromuscular junction: a specific type of synapse between a motor neuron and a muscle fiber (though not a direct synonym for all synapses).

Related Idioms

• "Firing on all synapses": (informal, figurative) functioning at maximum mental capacity; being highly alert or intelligent.
  • After a good night's sleep, her brain was firing on all synapses. (She was thinking clearly and quickly.)

Notes on Usage

• "Synapses" is almost always used in the plural when referring to the general concept of neural connections, as they occur in vast numbers. The singular "synapse" is used when discussing a specific junction.
• The term is primarily technical and belongs to neuroscience, biology, and medicine; it is rarely used in everyday conversation outside of academic or scientific contexts.