-ism

1. Action; process; practice: terrorism.
2. Characteristic behavior or quality: heroism.
3. 1. State; condition; quality: pauperism.
   2. State or condition resulting from an excess of something specified: strychninism.
4. Distinctive or characteristic trait: Latinism.
5. 1. Doctrine; theory; system of principles: pacifism.
   2. An attitude of prejudice against a given group: racism.

[Middle English -isme, from Old French, from Latin -ismus, from Greek -ismos, n. suff..]

1. Action, process; practice: vegetarianism.
2. Characteristic behavior or quality: puerilism.
3. State; condition; quality: senilism.
4. State or condition resulting from an excess of something specified: strychninism.
5. Doctrine; theory; system of principles: Darwinism.