Hums are those about whom Allah, the Exalted and Glorious, revealed this verse:" Then hasten to where the people hasten." She (further) said: The people hastened on from 'Arafat, whereas Hums hastened from Muzdalifa, and said: We'do not hasten but from Haram. But when this (verse) was revealed:" Hasten on from that (place) where the people hasten on," they (the Quraish) then went to 'Arafat.
Sahih Muslim Book 15, Hadith 164