From The Collaborative International Dictionary of English v.0.48:
Ism \Ism\, n. [See ism, above.]
A doctrine or theory; especially, a wild or visionary theory.
--E. Everett.
[1913 Webster]
The world grew light-headed, and forth came a spawn of
isms which no man can number. --S. G.
Goodrich.
Ismaelian
From The Collaborative International Dictionary of English v.0.48:
-ism \-ism\ [F. -isme, or L. -ismus, Gr. ?.]
A suffix indicating an act, a process, the result of an act
or a process, a state; also, a characteristic (as a theory,
doctrine, idiom, etc.); as, baptism, galvanism, organism,
hypnotism, socialism, sensualism, Anglicism.
[1913 Webster]