ETYM Latin atomus, Greek, uncut, indivisible; a priv. + temnein to cut: cf. French atome. Related to Tome.
(formerly) ultimate unit of matter; smallest particle of element that can exist alone or as a constituent of molecule; any very small thing or quantity.
Smallest unit of matter that can take part in a chemical reaction, and which cannot be broken down chemically into anything simpler. An atom is made up of protons and neutrons in a central nucleus surrounded by electrons (see atomic structure). The atoms of the various elements differ in atomic number, atomic weight, and chemical behavior. There are 109 different types of atom, corresponding with the 109 known elements as listed in the periodic table of the elements.
Atoms are much too small to be seen even by even the most powerful optical microscope (the largest, cesium, has a diameter of 0.0000005 mm/0.00000002 in), and they are in constant motion. However, modern electron microscopes, such as the scanning tunneling microscope (STM) and the atomic force microscope (AFM), can produce images of individual atoms and molecules.
1. (Nontechnical usage) A tiny piece of anything; SYN. molecule, particle, mote, speck.
2. (Physics and chemistry) The smallest component of an element having the chemical properties of the element.

ETYM Latin corpusculum, dim. of corpus.
1. A single cell, such as a blood cell.
2. A cluster of cells.
3. A small body.
4. Particle; minute portion or body.

(Alternate spelling: atomisation).
1. Annihilation by reducing something to atoms; SYN. atomisation.
2. Separating something into fine particles; SYN. atomisation, fragmentation.

ETYM Cf. French atomisme.
1. The doctrine of atoms.
2. Belief that the universe consists of small indivisible particles.
3. Theory of atoms.

Device that produces a spray of fine droplets of liquid. A vertical tube connected with a horizontal tube dips into a bottle of liquid, and at one end of the horizontal tube is a nozzle, at the other a rubber bulb. When the bulb is squeezed, air rushes over the top of the vertical tube and out through the nozzle. Following Bernoulli's principle, the pressure at the top of the vertical tube is reduced, allowing the liquid to rise. The air stream picks up the liquid, breaks it up into tiny drops, and carries it out of the nozzle as a spray. Scent spray, paint spray guns, and carburetors all use the principle of the atomizer.A dispenser that turns a liquid (such as perfume) into a fine spray; SYN. atomiser, spray, sprayer.

Alternate (chiefly British) spelling of atomize.

(Alternate spelling: atomise).
1. To break up into small particles; of liquids or solids.
2. To spray very finely.

(Alternate spelling: atomise).
1. To break up into small particles; of liquids or solids.
2. To spray very finely.