The union or the intersection or the meeting of two rays having the same end points form an angle. It is just the unit of measure used to measure a Non Physical unit, means like angles, and solid angles which are usually measured in steradians etc.,
Flexing is the medical term meaning decreasing an angle as in bending a joint.
somthing
The value of something
Oblique means slanted or at an angle.
(of an angle) more than 90° and less than 180°.
angle
angle under 90 degrees
surface area
double penatration (flip thing
A micrometre is a thousandth of a metre.
Yes, it is a prefix meaning a thousand.
"Perpendicular" means at an angle of 90° to a given line, plane, or surface.