Definitions for "Diglossia"
A relatively stable linguistic situation in which two different variet­ies of a single language co-occur in a linguistic community, one (the `high' variety) usually being the more formal and presti­gious; the other (the `low') variety being used in more informal settings, chiefly in conversation. Examples: Greek Katharvousa (`high') and Dhimo­tiki (`low'); Arabic al-fua and al-`amm_yah; in Swiss Ger­man: Hochd­eu­tsch and Schwyzerd­tsch. In a wider sense also a co-occur­rence of two unrelated lan­guages such as Spanish and Guarani in Para­guay.
the situation in which two forms of the same language are spoken by people in the same language community, depending on the social situation.
Diglossia is a situation where there are two versions of a language with very different uses, a High form for official occasions and a Low form for everyday life, as in the difference between High German and Swiss German in German-speaking areas of Switzerland
Keywords:  switching, code, see
See Code Switching