What is the difference in meaning between reciting "uffin" with a tanween, "uffa" with a fatḥa, and "uffi" with a kasra, in His Almighty's saying: "So do not say to them, 'uff!'"?

The word (أُفٍّ) has several linguistic variations, the most eloquent being ten, and the most famous three, which were recited by the ten Qira'at reciters. Abu Ja'far, Nafi', and Hafs from 'Asim recited with a kasra on the fa and tanwin: "أُفٍّ" (uff). Ibn Kathir, Ibn 'Amir, and Ya'qub recited with a fatha on the fa: "أُفَّ" (uffa). The meaning of the word is singular: dislike and contempt. Its origin is the dirt found in skin folds and on fingers, and it is also said its origin is foul smell.

The meaning of the verse is: Do not say anything to them that indicates the slightest displeasure. It was narrated from Mujahid: If you see in their old age what they used to see from you in your youth concerning dirt, do not loathe them and say: uff.

It is also reported in a marfu' hadith from Ali (may Allah be pleased with him): "Had Allah known of any act of disobedience worse than 'uff', He would have mentioned it. So, let the dutiful son do whatever he wishes, for he shall not enter the Fire; and let the disobedient son do whatever he wishes, for he shall not enter Paradise."