subtend

/səbˈtɛnd/
verb
  1. (of a line, arc, or side) to be opposite to and form the boundary of an angle or geometric figure.
    • The chord of a circle subtends an arc that is twice the angle at the center.
    • The base of the isosceles triangle subtends the vertex angle.
    • In a triangle, the side opposite an angle is said to subtend that angle.
Synonyms
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