The state or condition of being curvilinear.(noun)
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Use "curvilinearity" in a sentence
"We suspected that most people would not spontaneously think in terms of this curvilinearity and would, in fact, think that fuel consumption decreases as a linear function of MPG."
"He – and his celebration of curvilinearity one of the faultlines in 20th century art – remain top in my design canon."
"He humps himself over the open volume and begins to display that unerring curvilinearity of the spine that compels his mother to study braces and to fear that he will develop consumption."