the transporting of students by bus to schools outside their neighborhoods, especially as a means of achieving socioeconomic or racial diversity among students in a public school. Origin Expand 1885-90; bus 1 (v.) + -ing 1, spelled irregular with single s, perhaps to avoid association with buss
Translational symmetry of an object means that a particular translation does not change the object. For a given object, the translations for which this applies form a group, the symmetry group of the object, or, if the object has more kinds of symmetry, a subgroup of the symmetry group. 1 Geometry.
For other uses, see Reference (disambiguation). Reference is a relation between objects in which one object designates, or acts as a means by which to connect to or link to, another object. The first object in this relation is said to refer to the second object. The second object, the one to which the first object refers, is called the referent of the first object.