柯林斯詞典tangent /?t?nd??nt/ (tangents) 1. N-COUNT A tangent is a line that touches the edge of a curve or circle at one point, but does not cross it. 切線2. PHRASE If someone goes off on a tangent, they start saying or doing something that is not directly connected with what they were saying or doing before. 突然離題[V and N inflect] The conversation went off on a tangent. 談話突然偏離了正題。 返回 tangent劍橋詞典 tangent noun [C] (CIRCLE) a straight line that touches but does not cut into a curve 切線 tangent noun [C] (TRIANGLE) (written abbreviation tan) (in a triangle that has one angle of 90°) the ratio of the length of the side opposite an angle less than 90° divided by the length of the shorter of the two sides that are next to the angle 正切 比較cosine sine 習(xí)語go off on a tangent 返回 tangent