tangent

/ˈtændʒənt/

/ˈtandʒɪnt/

Other forms: tangents

A tangent is an entirely different topic or direction. When you want a break from geometry class, you might ask your teacher about his hobby of woodworking, a topic that's always good for a ten-minute tangent.

Tangent is mainly a mathematical term, meaning a line or plane that intersects a curved surface at exactly one point. The non-mathematical meaning of tangent comes from this sense of barely touching something: when a conversation heads off on a tangent, it's hard to see how or why it came up. When talking about history, someone suddenly brings last night's basketball game? Definitely a tangent.

Definitions of tangent

1. noun

   a straight line or plane that touches a curve or curved surface at only one point
   type of:

   straight line

   a line traced by a point traveling in a constant direction; a line of zero curvature
2. noun

   ratio of the opposite to the adjacent side of a right-angled triangle
   synonyms: tan

   type of:

   circular function, trigonometric function

   function of an angle expressed as a ratio of the length of the sides of right-angled triangle containing the angle
3. noun

   a message that departs from the main subject
   synonyms: aside, digression, divagation, excursus, parenthesis

   type of:

   content, message, subject matter, substance

   what a communication that is about something is about