Synapse: A specialized junction at which a neural cell (neuron) communicates with a target cell. At a synapse, a neuron releases a chemical transmitter that diffuses across a small gap and activates special sites called receptors on the target cell. The target cell may be another neuron or a specialized region of a muscle or secretory cell. Neurons can also communicate through direct electrical connections (electrical synapses).
Last Editorial Review: 5/13/2016