| Word | Definitions | Synonyms |
|---|---|---|
| atom | (noun) (physics and chemistry) the smallest component of an element having the chemical properties of the element | - |
| (noun) (nontechnical usage) a tiny piece of anything | Synonyms: corpuscle, molecule, mote, particle, speck | |
| diatom | (noun) microscopic unicellular marine or freshwater colonial alga having cell walls impregnated with silica | - |