semiangle

plural semiangles

1. geometryan angle of half a given size
2. The angle formed between the axis of a cone and a line drawn from the apex of the cone to the edge of its base.

   Variations in cone semiangle had no significant effects on the longitudinal stability at the two test Mach numbers .

   1963, Cuyler W. Brooks, Charles D. Trescot, Transonic Investigation of the Effects of Nose Bluntness, Fineness Ratio, Cone Angle, and Base Shape on the Static Aerodynamic Characteristics of Short Blunt Cones at Angles of Attack to 180°, page 10

   2 more examples

   The results show that the optimum cone semiangle decreases slightly when the Mach number increases and, in the range of Mach numbers considered, is in the range of 22° to 25° for supersonic entrance flow.

   1954, United States. National Advisory Committee for Aeronautics, Report, page 25

   The author's theory is almost perfect for 5° semiangle, is good for M_∞ ≤ 2 with 10° semiangle, and is beginning to be a serious overestimate for 15° semiangle.

   1954, M. J. Lighthill, Higher Approximations in Aerodynamic Theory, page 131