Webster's Revised Unabridged Dictionary · 1913

-gen

-gen

[(1) From Greek -gen-, from the same root as ge`nos race, stock (see Genus). (2) From Greek suffix -genh`s born. Compare French -gène.]

1.
A suffix used in scientific words in the sense of producing, generating: as, amphigen, amidogen, halogen.
2.
A suffix meaning produced, generated; as, exogen.