different between particularity vs particularism

English

From Middle French particularité, from Late Latin particularitas

particularity (countable and uncountable, plural particularities)

(uncountable) The condition of being particular; attention to detail; fastidiousness
(countable) A particular thing; a peculiarity

From particular +? -ism, after French particularisme.

particularism (countable and uncountable, plural particularisms)

(theology) The principle that only certain people are chosen by God for salvation.
An exclusive focus on a particular group, area, sect etc.
(politics) The principle that individual states, races of a federation etc. may act independently of a central authority.
- 2011, Norman Davies, Vanished Kingdoms, Penguin 2012, p. 221:
  Despite the dominance of Castile and the stream of centralizing measures flowing from the new capital in Madrid, Aragonese particularism continued to make itself felt right up to the early eighteenth century.

From French particularisme

particularism n (uncountable)

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