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
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"
(chemistry) a process in which one substance permeates another; a fluid permeates or is dissolved by a liquid or solid
(physics) the process in which incident radiated energy is retained without reflection or transmission on passing through a medium; "the absorption of photons by atoms or molecules"
a narrow strip of wood on the neck of some stringed instruments (violin or cello or guitar etc) where the strings are held against the wood with the fingers
a high-pitched woodwind instrument; a slender tube closed at one end with finger holes on one end and an opening near the closed end across which the breath is blown
a groove or furrow in cloth etc (particularly a shallow concave groove on the shaft of a column)