Movement

I think it could be either:

Which length description are you looking for?:

ism

'movement' is the definition.
(I've seen this in another clue)

This is all the clue.

(Other definitions for ism that I've seen before include "specific doctrine" , "Belief system" , "Informally, any doctrine or practice" , "Informally a doctrine, or suffix for one" , "Informal doctrine found in Bismarck" .)

I've seen this clue in The New York Times.

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