• رَطْب
• رُطَب

Appears 2 times in the Quran.

1. 6:59 وَعِندَهُۥ مَفَاتِحُ ٱلْغَيْبِ لَا يَعْلَمُهَآ إِلَّا هُوَ وَيَعْلَمُ مَا فِى ٱلْبَرِّ وَٱلْبَحْرِ وَمَا تَسْقُطُ مِن وَرَقَةٍ إِلَّا يَعْلَمُهَا وَلَا حَبَّةٍ فِى ظُلُمَٰتِ ٱلْأَرْضِ وَلَا رَطْبٍ وَلَا يَابِسٍ إِلَّا فِى كِتَٰبٍ مُّبِينٍ

   And with Him are the keys of the unseen treasures-- none knows them but He; and He knows what is in the land and the sea, and there falls not a leaf but He knows it, nor a grain in the darkness of the earth, nor anything green nor dry but (it is all) in a clear book.
   

2. 19:25 وَهُزِّىٓ إِلَيْكِ بِجِذْعِ ٱلنَّخْلَةِ تُسَٰقِطْ عَلَيْكِ رُطَبًا جَنِيًّا

   And shake towards you the trunk of the palmtree, it will drop on you fresh ripe dates: