-on

suff.

1. 1. Subatomic particle: baryon.
   2. Unit; quantum: photon.
2. Basic hereditary unit: codon.

[From ION.]

-on²
suff.
Inert gas: radon.

[New Latin, from (ARG)ON.]

-on³
suff.
A chemical compound that is not a ketone or a compound that contains oxygen in a carbonyl group: parathion.

[Alteration of -ONE.]

suff.

1. A subatomic particle: neutron.
2. A unit: photon.
3. A basic hereditary unit: codon.

–on
suff.

Inert gas: radon.

–on
suff.

A chemical compound that is not a ketone or a compound that contains oxygen in a carbonyl group: parathion.