| Diatom | n. [ Gr. dia`tomos cut in two. See Diatomous. ] 1. (Bot.) One of the Diatomaceæ, a family of minute unicellular Algæ having a siliceous covering of great delicacy, each individual multiplying by spontaneous division. By some authors diatoms are called Bacillariæ, but this word is not in general use. [ 1913 Webster ] 2. A particle or atom endowed with the vital principle. [ 1913 Webster ] The individual is nothing. He is no more than the diatom, the bit of protoplasm. Mrs. E. Lynn Linton. [ 1913 Webster ] |
| diatomaceous | a. [ See Diatomous. ] consisting of or containing diatoms or their fossils; as, diatomaceous earth (used as a component of dynamite). [ PJC ] |
| diatomaceous earth | (Geol.), a deposit of fine, usually white, siliceous material, composed mainly of the shells of the microscopic plants called diatoms; also called infusorial earth, kieselguhr, and diatomite. It is used in polishing powder, and in the manufacture of dynamite. [ 1913 Webster +PJC ] |
| diatomic | a. [ Pref. di- + atomic. ] (Chem.) (a) Containing two atoms. (b) Having two replaceable atoms or radicals. [ 1913 Webster ] |
| Diatomophyceae | n. a class of marine and freshwater eukaryotic algae comprising the diatoms.
Syn. -- Bacillariophyceae, class Bacillariophyceae, class Diatomophyceae. [ WordNet 1.5 ] |
| Diatomous | a. [ Gr. dia`tomos cut through, fr. diate`mnein to cut through; dia` through + te`mnein to cut. Cf. Diatom. ] (Min.) Having a single, distinct, diagonal cleavage; -- said of crystals. Mohs. [ 1913 Webster ] |
