Carnation Revolution

Etymology
. So named because a woman who had carnations handed them out to soldiers in the early hours of the coup, and they were placed in gun barrels and became a symbol of the peacefulness of the coup.

Proper noun

 * 1)  A revolution and military coup by left-leaning military officers that overthrew the colonialist and authoritarian Estado Novo on 25 April 1974 in Lisbon, Portugal, leading to major cultural and political changes.