If you want to refer to the pronunciation of professional speakers or foreign language model pronunciation the term is Standardaussprache or Standardlautung for "die gesprochene Form der deutschen Hoch- oder Standardsprache" according to Duden-Aussprachewörterbuch. It was defined by Max Mangold as codification of a norm.

The criteria he established were (I quote from the preface of the 3rd edition) that it is "überregional" i.e. it does not contain regional or dialect pronunciation forms; "einheitlich", i.e. it contains no or only a minimum of variation ; "schriftnah", i.e. it orients towards the written standard; "deutlich", i.e. the sounds are more distinct than in colloquial speech; "sie orientiert sich an der Sprechwirklichkeit", i.e. the model pronunciation is not as artificial as its predecssor "Bühnenaussprache".

Whereas the first four principels seem rather clear and well described one might have second thoughts as to the last principle. It seems more descriptive than the others. Usually I tell my students that it is the language they can hear from news speakers in ARD or ZDF, but those have been trained to speak Standardaussprache... circular, I know,

For the sake of clearity I find it advantageous to think of a Standard as an abstract norm that speakers orient towards in certain situations/registers, e.g. giving a public speech in an non regional context. Of course, we can then start discussing who has the insight, power (you name it) to set the norm.

Wahrig Deutsches Wörterbuch (1975) defines Hochdeutsch, inter alia, "auf der Sprache der sächs. Kanzleien beruhende deutsche Schriftsprache." The term, unfortunately, is not found in "Geschichtliche Grundbegriffe, Historisches Lexikon zur politisch-sozialen Sprache in Deutschland" (2004).

I have always referred to the language I learned in Germany as Universitätsdeutsch, a term I coined and have never heard anyone else use, although everyone I have met understands what I mean by it.  I can think of no better description of what is spoken at every institution of higher learning in Germany by every native German speaker. Students from all regions do their utmost best at the Uni to hide their often provincial roots by speaking a clear and uniform Universitätsdeutsch, (except when untereinander), even if they have to learn it for the first time at the Uni.  The term is best reserved for university settings. I suppose another formulation might be Dudendeutsch, a term I have never heard and just now made up, but expect to be universally understood, and would be highly precise, although a moving target.  In the end, I suggest  to use Hochdeutsch as the standard term, universally understood to refer to the language that one should write and speak to be understood by all, to be accepted in government and business, to advance a career, and to avoid being thought of as a Hinterwäldler. Standarddeutsch might do, but Hochdeutsch is hardly standard.

To make things even less clear, when the wall came down, one could buy east-west dictionaries, like Birgit Wolf's "Sprache in der DDR, Ein Wörterbuch." or "Deutsch-Deutsch, Ein Satirisches Wörterbuch" von Ernst Röhl, a historical and hysterical treasure.

I would not rely on German media to define Hochdeutsch, just as I would not suggest that anyone try to learn English from American media.  At least in the U.S., the language spoken by the media is atrocious. In the U.S, the media are in the process of destroying the English language.

If this doesn't help, I hope it at least entertains.

It is hochdeutsche which means Standard Language. Hoch means high and standard and duetsche is germany language

I only have something something anecdotal: German classes that I attended at Goethe Institute uses the term Hochdeutsch.

If you want to refer to the pronunciation of professional speakers or foreign language model pronunciation the term is Standardaussprache or Standardlautung for "die gesprochene Form der deutschen Hoch- oder Standardsprache" according to Duden-Aussprachewörterbuch. It was defined by Max Mangold as codification of a norm.

The criteria he established were (I quote from the preface of the 3rd edition) that it is "überregional" i.e. it does not contain regional or dialect pronunciation forms; "einheitlich", i.e. it contains no or only a minimum of variation ; "schriftnah", i.e. it orients towards the written standard; "deutlich", i.e. the sounds are more distinct than in colloquial speech; "sie orientiert sich an der Sprechwirklichkeit", i.e. the model pronunciation is not as artificial as its predecssor "Bühnenaussprache".

Whereas the first four principels seem rather clear and well described one might have second thoughts as to the last principle. It seems more descriptive than the others. Usually I tell my students that it is the language they can hear from news speakers in ARD or ZDF, but those have been trained to speak Standardaussprache... circular, I know,

For the sake of clearity I find it advantageous to think of a Standard as an abstract norm that speakers orient towards in certain situations/registers, e.g. giving a public speech in an non regional context. Of course, we can then start discussing who has the insight, power (you name it) to set the norm.

Danke Maria!

Inspired me to check my meager Duden collection. Noteworthy is that volume 9 (6th edition, 2007), entitled "Richtiges und gutes Deutsch" studiously avoids the term Hochdeutsch. In the Vorwort, the Dudenredaktion [Duden editorial staff] speaks instead of "richtiges und gutes Deutsch" [correct and good German]. Duden "kommt...nicht ohne eine normativ geregelte Standardsprache aus." [Duden could not avoid a normative structured standard language.] "Diese ist eine unverzichtbare Grundlage fur die allgemeine Vertständigung im Zeitalter der Kommunikations- und Informationsgesellschaft." [This is an indispensable foundation for common understanding in the age of the communications- and information society].

However: "Dialekte, lokale Umgangssprachen oder Gruppensprachen werden damit nicht abgewertet; sie haben ihre eigenen wichtigen Funktionen und tragen auf ihre Weise zur Lebendikgkeit und Vielfalt der Sprache bei." [Dialects, local colloquial language or group language are not thereby discounted; they have their own important functions and contribute in their own way to the vitality and variety of the language.]

"Ein vernünftiger Umgang mit sprachlichen Normen setzt sowohl die möglichst genaue Kenntnis dieser Normen als auch eine aufgeschlossene Beurteilung von Regelabweichungen voraus."  [A rational interaction with linguistic norms assumes both a reasonably exact knowledge of these norms and an open-minded appreciation of deviations from the rules.] "'Richtiges und gutes Deutsch' berücksichtigt beides" ["Correct and good German" considers (respects, includes) both.

So, while Hochdeutsch may form the structural foundation of correct and good German. it is just that and no more. Correct and good German goes beyond it.

Why not use the readily understandable name: Spoken German?

Thank you for the answers! 

I knew most of the expressions and the explanations helped me to reflect on the language varieties of German. I believe that the terms are correct, depending on the context of use (at university, by lay people, by professional speakers ...)

However, I have to choose one for my study in Brazil. The participantes will be Brazilians, speakers of German as a foreign language and will read words and sentences in German. What do you suggest? I tend to choose Standard German, but I still have questions.