definition of
fluidity

[1] #1 fluidity n. [fluidness, liquidity, liquidness, runniness] the property of flowing easily; "adding lead makes the alloy easier to cast because the melting point is reduced and the fluidity is increased"; "they believe that fluidity increases as the water gets warmer". wn

[2] #2 fluidity n. [fluidness] a changeable quality; "a charming Oriental fluidity of manner"; "a certain fluidness in his perception of time made him an unpredictable colleague"; "demographers try to predict social fluidity". wn