sub·​tend | \ səb-ˈtend How to pronounce subtend (audio) \
subtended; subtending; subtends

Definition of subtend

transitive verb

1a : to be opposite to and extend from one side to the other of a hypotenuse subtends a right angle
b : to fix the angular extent of with respect to a fixed point or object taken as the vertex a central angle subtended by an arc the angle subtended at the eye by an object of given width and a fixed distance away
c : to determine the measure of by marking off the endpoints of a chord subtends an arc
2a : to underlie so as to include
b : to occupy an adjacent and usually lower position to and often so as to embrace or enclose a bract that subtends a flower

Examples of subtend in a Sentence

Recent Examples on the Web Before 1967, political borders, however provisional, subtended cultural ones: sovereignty derived from international recognition and the consent of the governed. Bernard Avishai, The New Yorker, "How the Six-Day War Changed Israel’s Mind," 5 June 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'subtend.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of subtend

circa 1560, in the meaning defined at sense 1a

History and Etymology for subtend

Latin subtendere to stretch beneath, from sub- + tendere to stretch — more at thin

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Time Traveler for subtend

Time Traveler

The first known use of subtend was circa 1560

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Cite this Entry

“Subtend.” Dictionary, Merriam-Webster, Accessed 26 Nov. 2020.

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