adj. 1 remaining in one place, not moving (hit a stationary car). 2 not meant to be moved; not portable (stationary troops; stationary engine). 3 not changing in magnitude, number, quality, efficiency, etc. (stationary temperature). 4 (of a planet) having no apparent motion in longitude. stationary air air remaining in the lungs during ordinary respiration. stationary bicycle a fixed exercise-machine resembling a bicycle. stationary point Math. a point on a curve where the gradient is zero. stationary wave = standing wave. stationariness n.
[ ME f. L stationarius (as STATION) ]