In the nervous system, a synapse is a structure that permits a neuron (or nerve cell) to pass an electrical or chemical signal to another neuron or to the target effector cell.
https://github.com/davepinch/pinchy.cc/blob/master/content/topics/biology/topics/synapse/en.wikipedia.org.md
Homer mentions Boötes in the Odyssey as a celestial reference for navigation, describing it as “late-setting” or “slow to set”.