(meteorology) rapid inward circulation of air masses about a low-pressure center; circling counterclockwise in the northern hemisphere and clockwise in the southern
a question raised for consideration or solution; "our homework consisted of ten problems to solve"
a state of difficulty that needs to be resolved; "she and her husband are having problems"; "it is always a job to contact him"; "urban problems such as traffic congestion and smog"
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"