極微
Từ Điển Thuật Ngữ Phật Học Hán Ngữ
An atom, especially as a mental concept, in contrast with 色聚之微, i.e. a material atom which has a center and the six directions, an actual but imperceptible atom; seven atoms make a 微塵 molecule, the smallest perceptible aggregation, called an aṇu 阿莬 or 阿拏; the perceptibility is ascribed to the deva-eye rather than to the human eye. There is much disputation as to whether the ultimate atom has real existence or not, whether it is eternal and immutable and so on.