the period of time that it takes for a planet (as, e.g., Earth or Mars) to make a complete revolution around the sun; "a Martian year takes 687 of our days"
a period of time containing 365 (or 366) days; "she is 4 years old"; "in the year 1920"
a period of time occupying a regular part of a calendar year that is used for some particular activity; "a school year"
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
the quality imparted to voiced speech sounds by the action of the resonating chambers of the throat and mouth and nasal cavities
a vibration of large amplitude produced by a relatively small vibration near the same frequency of vibration as the natural frequency of the resonating system
an excited state of a stable particle causing a sharp maximum in the probability of absorption of electromagnetic radiation