asymptote

n. straight line approaching but never intercepts a curve (Mathematics)

An asymptote is a straight line or curve A to which another curve B (the one being studied) approaches closer and closer as one moves along it. As one moves along B, the distance between it and the asymptote A tends to become smaller and smaller overall, and eventually never becomes longer than any specified distance. A curve may or may not touch or cross its asymptote. In fact, the curve may intersect the asymptote an infinite number of times, but its maximal deviation from the asymptote keeps getting smaller.
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Noun
1. a straight line that is the limiting value of a curve; can be considered as tangent at infinity; "the asymptote of the curve"
(hypernym) straight line

n. asymptote, straight line approaching but never intercepts a curve (Mathematics)

n. asymptote, straight line approaching but never intercepts a curve (Mathematics)