a very small piece
smallest possible amount
any of a number of usually short words that are not as important in a sentence as the subject, verb, etc.
The fat droplets have been broken up into much smaller particles.
出自: B. Spock
Mud..formed from the still finer particles of material carried out from the coast.
出自: A. Hardy
In the shafts of light..she could see particles moving.
出自: E. Figes