(ن) رَبَا يَرْبُوْ رُبُوًّا وَرِبَاءًrabā yarbū rubuwwan wa-ribāʾan: for something to rise above its place, to grow, to increase. ﴿اهْتَزَّتْ وَرَبَتْ﴾ (Al-Ḥajj 22:5)
رَابٍrāb (active participle, ism fāʿil, on the pattern of فَاعِلٌfāʿil): swelling, rising. ﴿فَاحْتَمَلَ السَّيْلُ زَبَدًا رَّابِيًا﴾ (Ar-Raʿd 13:17)
رِبٰواribāā (noun, ism dhāt): a thing increased or swollen; usury. ﴿وَاَحَلَّ اللّٰهُ الْبَيْعَ وَحَرَّمَ الرِّبٰوا﴾ (Al-Baqarah 2:275)
رَبْوَةٌrabwah (noun, ism dhāt): elevated ground, a hill. ﴿كَمَثَلِ جَنَّةٍۢ بِرَبْوَةٍ﴾ (Al-Baqarah 2:265)
اَرْبٰىarbā (elative, ism tafḍīl): more increased, more numerous. ﴿اَنْ تَكُوْنَ اُمَّةٌ هِيَ اَرْبٰى مِنْ اُمَّةٍ﴾ (An-Naḥl 16:92)
Form IV (ifʿāl) اَرْبٰى يُرْبِيْ اِرْبَاءًarbā yurbī irbāʾan: to raise, to increase. ﴿وَيُرْبِي الصَّدَقٰتِ﴾ (Al-Baqarah 2:276)
Form II (tafʿīl) رَبّٰى يُرَبِّيْ تَرْبِيَةًrabbā yurabbī tarbiyatan: to keep raising by degrees, i.e. to rear, to bring up. ﴿كَمَا رَبَّيٰنِيْ صَغِيْرًا﴾ (Al-Isrāʾ 17:24)