Word Study
subtend
CIDE DICTIONARY
subtend, v. t. [L. subtendere; sub under + tendere to stretch, extend. See Tend.].
To extend under, or be opposed to; as, the line of a triangle which subtends the right angle; the chord subtends an arc. [1913 Webster]
OXFORD DICTIONARY
subtend, v.tr.
1 a (usu. foll. by at) (of a line, arc, figure, etc.) form (an angle) at a particular point when its extremities are joined at that point. b (of an angle or chord) have bounding lines or points that meet or coincide with those of (a line or arc).
2 Bot. (of a bract etc.) extend under so as to embrace or enfold.
1 a (usu. foll. by at) (of a line, arc, figure, etc.) form (an angle) at a particular point when its extremities are joined at that point. b (of an angle or chord) have bounding lines or points that meet or coincide with those of (a line or arc).
2 Bot. (of a bract etc.) extend under so as to embrace or enfold.
Etymology
L subtendere (as SUB-, tendere stretch)
THESAURUS
subtend
bump heads, confront, contend, contrapose, contraposit, contrast, counteract, face, front, lie opposite, match, meet head-on, oppose, polarize, pose against, put in opposition, set over against, stand opposed, stand oppositeFor further exploring for "subtend" in Webster Dictionary Online