The word "Qur'ān" was commonly used in medieval Jewish Arabic to refer to established liturgical reading traditions of the Hebrew Bible.
"And the consensus among those (diaspora Jewish communities) just mentioned is that the pronunciation of the Land of Israel is the original and it is what we know as 'The Tiberian Reading'"
ובאגמאע מן דכר אן טריקה ארץ ישראל הי אלאצל והי אלדי יסמונהא אלקראן אלטבראני
Transcribed into Arabic graphemes, the effect is almost jarring:
وبإجماع من ذُكر أنّ طريقة ارص يسرائيل هي الأصل وهي الذي يسمونها القرآن الطبراني.
That's not an entirely rhetorical question. If I'm missing something I'd love to know.
דכר פי מאסרתה וקאל אן פי אלקראן ארבעה
בלשון מרובה דגשין
"Made a note in his Masorah to the effect that there are four cases of intense dagesh in the Bible (=קראן)"