1. (of water or air) cease to flow or move; become stagnant.Similarstop flowingbecome stagnantbecome trappedstandbecome foulbecome stalefesterputrefyOppositeflow
▪ cease developing; become inactive or dull:"teaching can easily stagnate into a set of routines"Similarbecome stagnantdo nothingstand stillbe sluggishlie dormantbe inertlanguishdeclinedeterioratefallOppositeriseboom
Word Originmid 17th century: from Latin stagnat- ‘settled as a still pool’, from the verb stagnare, from stagnum ‘pool’.