Mathematics and Physics Glossary

Tabular difference (Math.), the difference between two consecutive numbers in a table, sometimes printed in its proper place in the table.

Tail of a comet (Astron.), a luminous train extending from the nucleus or body, often to a great distance, and usually in a direction opposite to the sun.

Tangent, n. (Geom.) 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.

Tangent, a. Touching; touching at a single point; specifically (Geom.) meeting a curve or surface at a point and having at that point the same direction as the curve or surface; said of a straight line, curve, or surface; as, a line tangent to a curve; a curve tangent to a surface; tangent surfaces.

-- Tangent curve, n. (Trig.) the graph showing how the size of value of the tangent of an angle changes with the size of the angle.

-- Tangent plane (Geom.), a plane which touches a surface in a point or line.

Tangental, a. (Geom.) Tangential.