molecule, atom, particle, speck, grain

1. A particle, such as an electron, a proton, or a neutron, having half-integral spin and obeying statistical rules requiring that not more than one in a set of identical particles may occupy a particular quantum state.
   費(fèi)密子一種如電子、質(zhì)子或中子等自旋為半整數(shù)的基本粒子，具有一種使得不可能有多于一個(gè)的粒子占有任何一個(gè)特殊的量子力學(xué)態(tài)的量子力學(xué)對(duì)稱性
2. There wasn't a particle of truth in what he said.
   他說(shuō)的沒(méi)有一點(diǎn)真話。
3. We can see the dust particles floating in the sunlight clearly.
   我們可以很清楚地看到陽(yáng)光下的灰塵顆粒。