Peaceful
Middle English: from Old French pais, from Latin pax, pac- ‘peace’.
wiktionary
From Middle English peesful, pesful, paisful, pesefull, equivalent to peace + -ful.
Derived from the derogatory term religion of peace, which is used against Islam itself for its association with violent attacks by more-extreme members, and alleged support and lack of condemnation against them by certain Muslim communities.
etymonline
peaceful (adj.)
early 14c., pesful, peesfull, paisful, "inclined to peace, friendly, pacific;" mid-14c. as "tranquil, calm, full of peace;" from peace + -ful. In reference to nonviolent methods of effecting social change, it is attested from 1876. Related: Peacefully; peacefulness. Peaceful coexistence (1920) originally was in regard to Soviet policy toward the capitalist West.
