The word حبة in the Quran

مَّثَلُ ٱلَّذِينَ يُنفِقُونَ أَمْوَٰلَهُمْ فِى سَبِيلِ ٱللَّهِ كَمَثَلِ حَبَّةٍ أَنۢبَتَتْ سَبْعَ سَنَابِلَ فِى كُلِّ سُنۢبُلَةٍ مِّا۟ئَةُ حَبَّةٍ وَٱللَّهُ يُضَٰعِفُ لِمَن يَشَآءُ وَٱللَّهُ وَٰسِعٌ عَلِيمٌ ۝٢٦١

The example of those who spend their wealth in the way of Allāh is like a seed [of grain] which grows seven spikes; in each spike is a hundred grains. And Allāh multiplies [His reward] for whom He wills. And Allāh is all-Encompassing and Knowing.

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 ۝٥٩

And with Him are the keys of the unseen; none knows them except Him. And He knows what is on the land and in the sea. Not a leaf falls but that He knows it. And no grain is there within the darknesses of the earth and no moist or dry [thing] but that it is [written] in a clear record.

وَنَضَعُ ٱلْمَوَٰزِينَ ٱلْقِسْطَ لِيَوْمِ ٱلْقِيَٰمَةِ فَلَا تُظْلَمُ نَفْسٌ شَيْـًٔا وَإِن كَانَ مِثْقَالَ حَبَّةٍ مِّنْ خَرْدَلٍ أَتَيْنَا بِهَا وَكَفَىٰ بِنَا حَٰسِبِينَ ۝٤٧

And We place the scales of justice for the Day of Resurrection, so no soul will be treated unjustly at all. And if there is [even] the weight of a mustard seed, We will bring it forth. And sufficient are We as accountant.

يَٰبُنَىَّ إِنَّهَآ إِن تَكُ مِثْقَالَ حَبَّةٍ مِّنْ خَرْدَلٍ فَتَكُن فِى صَخْرَةٍ أَوْ فِى ٱلسَّمَٰوَٰتِ أَوْ فِى ٱلْأَرْضِ يَأْتِ بِهَا ٱللَّهُ إِنَّ ٱللَّهَ لَطِيفٌ خَبِيرٌ ۝١٦

[And Luqmān said], "O my son, indeed if it [i.e., a wrong] should be the weight of a mustard seed and should be within a rock or [anywhere] in the heavens or in the earth, Allāh will bring it forth. Indeed, Allāh is Subtle and Aware.