D defs.my
Entry 1 sense Webster, 1913

Asymptote

/ăs'-əm-tōtˌ/ · As·ymp·tote · IPA /ˈæsɪmptoʊ̯t/
01 n. A line which approaches nearer to some curve than assignable distance, but, though infinitely extended, would never meet it. Asymptotes may…
  1. 1.
    A line which approaches nearer to some curve than assignable distance, but, though infinitely extended, would never meet it. Asymptotes may be straight lines or curves. A rectilinear asymptote may be conceived as a tangent to the curve at an infinite distance.(Math.)