tangent
nounUK /ˈtæn.dʒənt/
US /ˈtæn.dʒənt/
A tangent is a straight line that just touches a curve at one point.
The teacher drew a tangent to the circle on the board.
OTHER MEANINGS
2. A sudden change of subject in a conversation.
He went off on a tangent about his favorite movies.
3. In trigonometry, the ratio of the opposite side to the adjacent side in a right triangle.
We learned how to calculate the tangent of an angle today.
4. Completely different or unrelated to something.
Her comment was tangent to the main topic of the meeting.