the junction between two neurons (axon-to-dendrite) or between a neuron and a muscle; "nerve impulses cross a synapse through the action of neurotransmitters"
a major part of the central nervous system which conducts sensory and motor nerve impulses to and from the brain; a long tubelike structure extending from the base of the brain through the vertebral canal to the upper lumbar region
(physics) the force of attraction between all masses in the universe; especially the attraction of the earth's mass for bodies near its surface; "the more remote the body the less the gravity"; "the gravitation between two bodies is proportional to the product of their masses and inversely proportional to the square of the distance between them"; "gravitation cannot be held responsible for people falling in love"--Albert Einstein