The meaning is related to the majority of the Qur'an this is the explanation made by many scholars. If we assume that the Qur'an was revealed in at least seven Arabic languages this would mean that at least 15% was revealed in the language of Quraysh. 

However the prophet () transmitted it or it was revealed to him in 7 ahruf.
Further this is not a Hadith but a statement of a Sahabi (). Which might end up as an opinion.