Answer: subtending

AnswerCrossword Clue
subtending(of a line, arc, or figure) Form (an angle) at a particular point when straight lines from its extremities are joined at that point
subtending(of an angle or chord) Have bounding lines or points that meet or coincide with those of (a line or arc)
subtendingSUBTEND, to extend under or opposite to
subtending(of a bract) Extend under (a flower) so as to support or enfold it