The suffix -ism was first used to form a noun of action from a verb, as in baptism, from baptein, a Greek word meaning "to dip", and then extended to systems of belief.

The word ism was first used in 1680 and can be found in the works of such well-known writers as Thomas Carlyle, Julian Huxley and George Bernard Shaw. In the present day, it appears in the title of a standard survey of political thought, Today's ISMS by William Ebenstein, first published in the 1950s, and now in its 11th edition.

The -ism suffix can be used to express the following concepts:

  • doctrine, theory or religion (e.g. pacifism)
  • theory developed by an individual (e.g. Marxism)
  • political movement (e.g. feminism)
  • action, process or practice (e.g. terrorism)
  • characteristic, quality or origin (e.g. heroism)
  • state or condition (e.g. pauperism)
  • excess or disease (e.g. botulism)
  • prejudice or bias (e.g. racism)
  • characteristic speech patterns (e.g. Yogiism)

See also: list of Isms.