«وَيَوْمَ تَقُومُ السَّاعَةُ ... مَا لَبِثُوا غَيْرَ سَاعَةٍ»
On the day the Hour rises, they will say that they remained no longer than an hour.
Both occurrences of «ساعة» are nouns. The first denotes the final Hour, whereas the second indicates a short measure of time. The wording matches across the four formal dimensions but the meanings are different: this illustrates complete jinās of the mumāthil kind.
The classification is not simply based on spelling. Full formal identity is combined with the fact that both occurrences belong to the same broad grammatical class, unlike a pairing of a noun and a verb.