Diatom
Diatom (dī`ȧ*tom) , noun
[Greek dia`tomos cut in two. See Diatomous.]
1.
(Botany) One of the Diatomacea, a family of minute unicellular Alga having a siliceous covering of great delicacy, each individual multiplying by spontaneous division. By some authors diatoms are called Bacillaria, but this word is not in general use.
2.
A particle or atom endowed with the vital principle.
The individual is nothing. He is no more than the diatom, the bit of protoplasm.