während meaning and definition in german

1.) In the standard language, während is usually followed by a genitive:
* Ich wurde während eines Gesprächs angerufen. – "I was called during a conversation."
The dative case is used if the genitive would be indistinguishable from the nominative in form, which is the case with plural nouns not preceded by an article, determiner, or adjective:
* Ich wurde während Gesprächen angerufen. – "I was called during conversations."
The dative case is also used with pronouns that do not have a genitive form, and if a possessive genitive is preceding the referent of the preposition.
* Ich wurde während etwas Wichtigem angerufen. – "I was called during something important."
* Ich wurde während Peters langem Vortrag angerufen. – "I was called during Peter's long speech." (→ während Peters langen Vortrags is possible, but unusual)
2.) In the colloquial language, and occasionally in writing, it is common to use the dative case after während at all times, whereby the above peculiarities cease to apply. To some, the genitive may even sound pretentious in a private conversation.
* Ich wurde während einem Gespräch angerufen. – "I was called during a conversation."