/soh"leuh noyd', sol"euh-/ , n.
1. Elect. an electric conductor wound as a helix with small pitch, or as two or more coaxial helices, so that current through the conductor establishes a magnetic field within the conductor.
2. Also called solenoid switch . a switch controlled by such an arrangement, in which a metal rod moves when the current is turned on: used in automotive starting systems.
3. Meteorol. a space formed by the intersection of isobaric and isosteric surfaces.
[ 1825-35; solénoïde solén pipe, channel + F -oïde -OID ]