Meaning of ON in English

ON

adj.

Function: noun suffix

Etymology: from -on (in ion )

1 : subatomic particle <nucle on >

2 a : unit : quantum <phot on > <magnet on > b : basic hereditary component <cistr on > <oper on >

Merriam Webster Collegiate English Dictionary.      Merriam Webster - Энциклопедический словарь английского языка.