- (physics and biology) Forming nouns denoting subatomic particles (proton), quanta (photon), molecular units (codon), or substances (interferon).
- (biology, genetics) Forming names of things considered as basic or fundamental units, such as codon or recon.
- (chemistry) Forming names of noble gases and certain other elements (such as boron or carbon).
- Suffix variant for the illative singular, see -Vn.
Etymology 1 
Old French -on, a blending of Latin -ōnem (accusative singular of -ō, masculine appellative suffix), Frankish -on (accusative of -o, ending of masculine weak declension nouns), Frankish -in (diminutive suffix), and Frankish -ing (diminutive suffix for animals, via -enc, -enz).
- forming diminutives of things, inculding some animals
Etymology 2 
Derived terms 
- IPA: /on/
Usage notes 
- Member of the suffix cluster -n/-on/-en/-ön/