subtend

Meanings

1. To use an angle to delimit (mark off, enclose) part of a straight or curved line, for example an arc or the opposite side of a triangle.
2. To extend or stretch opposite something; to be part of a straight or curved line that is opposite to and delimits an angle.
3. To form the central angle of a circle underneath an arc.
4. To stand beneath or close to, as a bract at the base of a flower.

Etymology

From Latin subtendere, from sub (“under”) + tendere (“to stretch, extend”), itself a semantic loan from Ancient Greek ὑποτείνω (hupoteínō, “to subtend”), from which hypotenuse also derives. See tend.