A tangent line curve, or surface; specifically, that portion of the straight line tangent to a curve that is between the point of tangency and a given line, the given line being, for example, the axis of abscissas, or a radius of a circle produced. See Trigonometrical function, under Function.
- Making contact at a single point or along a line; touching but not intersecting.
- A line, curve, or surface meeting another line, curve, or surface at a common point and sharing a common tangent line or tangent plane at that point.
- Mathematics The trigonometric function of an acute angle in a right triangle that is the ratio of the length of the side opposite the angle to the length of the side adjacent to the angle.
- A sudden digression or change of course: went off on a tangent during the courtroom argument.
- Music An upright pin in a keyboard instrument, especially in a clavichord, that rises to sound a string when a key is depressed and stops the string at a preset length to set the pitch.