# Definition of *subtend* in English:

## subtend

Line breaks: sub|tendPronunciation: /sʌbˈtɛnd
/

### verb

[ with object]

- 1
*Geometry*(Of a line, arc, or figure) form (an angle) at a particular point when straight lines from its extremities are joined at that point:*the angle subtended by a string of length**r*at the centre of the sphereMore example sentences- The radian is a unit which connects the radius of an arc, the length of the arc and the angle subtended by the arc.
- The most common geometry for curved crystal diffraction is based on the Rowland circle principle, which relies on the well-known property of a circle that an arc segment subtends a constant angle for any point on the circle.
- Reticles are in the second focal plane, so as power is changed the angle subtended by the space between lines varies.

- 1.1(Of an angle or chord) have bounding lines or points that meet or coincide with those of (a line or arc).More example sentences
- This allowed him to calculate the chord subtended by angles of 36, 72, 60, 90 and 120.
- The Arc, Chord, Radius, Height, Angle, Apothem, and Area Suppose you have a segment of a circle, bounded by an arc of the circle and the chord subtending it.
- In fact Shen demonstrated a remarkable ability to view spatial arrangements and he gave an approximate formula for the length of a circular arc in terms of the chord subtending the arc.

- 2
*Botany*(Of a bract) extend under (a flower) so as to support or enfold it:*the main beauty is provided by the bracts which subtend the flowers*More example sentences- All flowers are subtended by a bract and two bracteoles.
- The flower meristems are produced acropetally by the inflorescence meristem and are subtended by bracts.
- The bract immediately subtends the sepal, partly enclosing it.

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Pronunciation: ˌastrə(ʊ)ˈgeɪʃ(ə)n

noun

(in science fiction) navigation in outer space