And Nuh said:
"My Lord! Leave not one of the disbelievers on the earth Dayyar!"
meaning, do not leave a single one of them on the face of the earth, not even a lone individual.
This is a method of speaking that gives emphasis to the negation.
Ad-Dahhak said, "Dayyar means one."
As-Suddi said, "Dayyar is the one who stays in the home."
So Allah answered his supplication and He destroyed all of those on the face of the earth who were disbelievers. He (Allah) even destroyed Nuh's (biological) son from his own loins, who separated himself from his father (Nuh).
He (Nuh's son) said,
سَأوِى إِلَى جَبَلٍ يَعْصِمُنِى مِنَ الْمَأءِ قَالَ لاَ عَاصِمَ الْيَوْمَ مِنْ أَمْرِ اللَّهِ إِلاَّ مَن رَّحِمَ وَحَالَ بَيْنَهُمَا الْمَوْجُ فَكَانَ مِنَ الْمُغْرَقِينَ
I will betake myself to some mountain, it will save me from the water.
Nuh said: "This day there is no savior from the decree of Allah except him on whom He has mercy."
And waves came in between them, so he (the son) was among the drowned. (11:43)
Allah saved the people of the ship who believed with Nuh, and they were those whom Allah commanded Nuh to carry with him.
Allah said,