-ism, -ismus

(Greek, ismos; Latin, ismus: a suffix: belief in, practice of, condition of, process, characteristic behavior or manner, abnormal state, distinctive feature or trait)

parasitism
1. Symbiosis in which one population (or individual) adversely affects the other, but cannot live without it.
2. Infection or infestation with parasites.
3. Etymology: "a hanger-on, a toady, a person who lives on others", from Middle French (about 1400 to 1600) parasite; from Latin parasitus, from Greek parasitos, "person who eats at the table of another"; from para-, "beside" + sitos, "food".

The scientific meaning of "animal" or "plant that lives on others" is first recorded in 1646.

parochialism
parricidism
Anyone who has a tendency or inclination to murder his/her father, or either parent, or other near relative.
particularism
partyism
paternalism
The principle or system of governing or controlling a country, group of employees, etc. in a manner suggesting a father’s relationship with his children.
pathomorphism
Abnormal morphology (the form and structure of a particular organism, organ, or part).
pathotropism
The tendency of drugs to pass into diseased areas.
patriotism
Love and loyal or zealous support of one’s own country
pedagogism, paedagogism, pedagoguism, paedagoguism (s) (noun); pedagogisms, paedagogisms, pedagoguisms, paedagoguisms (pl)
The character, spirit, or mannerof a teacher; the system of teaching.

Education today, more than ever before, must see clearly the dual objectives: education for living and educating for making a living.

—James Mason Wood
pedanticism (s) (noun), pedanticisms (pl)
A condition of being too concerned with what are thought to be the correct rules and details of something; such as, with language or the meanings of words.
pedantism (s) (noun), pedantisms (pl)
An excessive concern with minor details and rules or the display of academic learning.
pedobaptism, paedobaptism (s) (noun); pedobaptisms, paedobaptisms (pl)
The baptism of children or the religious rite of sprinkling on the forehead or the immersion in water, symbolizing purification or regeneration and admission to the Christian Church.
pedomorphism (s) (noun), pedomorphisms (pl)
Childhood characteristics in certain adult mammals.
pejorism (PEJ or riz'm)
1. The belief that the world is becoming worse.
2. The opinion or doctrine that everything in nature is growing worse.