Definition of 'fail-safe'. Word Frequency. fail-safe also failsafe. adjective. Something that is fail-safe is designed or made in such a way that nothing dangerous can happen if a part of it goes wrong. The camera has a built-in failsafe device which prevents it from working if the right signals aren't received.
A cuboid is a 3D shape. Cuboids have six faces, which form a convex polyhedron. Simply speaking, cuboids are made from 6 rectangles, which are placed at right angles. A cuboid that uses all square faces is a cube; if the faces are rectangles, other than squares, it looks like a shoe box. Properties of a Cuboid are:
A quadrilateral is any four sided polygon. There is no requirement for it to have any parallel sides. However a trapezoid (American English called a Trapezium in British English) is a quadrilateral with one set of parallel sides. A parallelogram is a quadrilateral with two sets of parallel sides.